Mathaversity Tutors

AP Calculus BC Sequences – Arithmetic, Geometric, Sandwich Theorem & Detailed Solutions

Understanding Sequences

Before studying infinite series in AP Calculus BC, we must understand sequences at a conceptual level.

A sequence is not just a list of numbers. It is a function whose inputs are positive integers:

a_n = f(n), \quad n = 1,2,3,\dots

Unlike regular functions defined on intervals, sequences are discrete. We evaluate them only at whole-number inputs.

Why Sequences Matter

In BC, sequences help us answer one central question:

What happens as n \to \infty ?

Does the sequence:

Understanding this behavior prepares us for infinite series.

Arithmetic Sequences — Linear Growth Behavior

Conceptual Understanding

An arithmetic sequence grows by adding the same amount each time.

If each term increases by 3, the pattern is predictable and linear.

Mathematically:
a_{n+1} - a_n = d
The constant d/katex] is called the <b>common difference</b>.</span> </div> </div> <div class="elementor-element elementor-element-fd1364c elementor-invisible elementor-widget elementor-widget-heading" data-id="fd1364c" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Deriving the Explicit Formula</h3> </div> </div> <div class="elementor-element elementor-element-6d7c7f0 elementor-invisible elementor-widget elementor-widget-heading" data-id="6d7c7f0" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Start with: a_1</span></span> </div> </div> <div class="elementor-element elementor-element-13d2be9 elementor-invisible elementor-widget elementor-widget-heading" data-id="13d2be9" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Then:</span> </div> </div> <div class="elementor-element elementor-element-7475ed8 elementor-invisible elementor-widget elementor-widget-heading" data-id="7475ed8" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_2 = a_1 + d</span></span> </div> </div> <div class="elementor-element elementor-element-2b1bb8c elementor-invisible elementor-widget elementor-widget-heading" data-id="2b1bb8c" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_3 = a_1 + 2d</span></span> </div> </div> <div class="elementor-element elementor-element-4cfd8a5 elementor-invisible elementor-widget elementor-widget-heading" data-id="4cfd8a5" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_4 = a_1 + 3d</span></span> </div> </div> <div class="elementor-element elementor-element-e04bd0f elementor-invisible elementor-widget elementor-widget-heading" data-id="e04bd0f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Notice the pattern:</span> </div> </div> <div class="elementor-element elementor-element-3fdd516 elementor-invisible elementor-widget elementor-widget-heading" data-id="3fdd516" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = a_1 + (n-1)d</span></span> </div> </div> <div class="elementor-element elementor-element-1bc776e elementor-invisible elementor-widget elementor-widget-heading" data-id="1bc776e" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example </h3> </div> </div> <div class="elementor-element elementor-element-2c44fbc elementor-invisible elementor-widget elementor-widget-heading" data-id="2c44fbc" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Let: <span class="katex-eq" data-katex-display="false">a_1 = 4, \quad d = 5</span></span> </div> </div> <div class="elementor-element elementor-element-bfd4005 elementor-invisible elementor-widget elementor-widget-heading" data-id="bfd4005" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Then:</span> </div> </div> <div class="elementor-element elementor-element-7f0fd92 elementor-invisible elementor-widget elementor-widget-heading" data-id="7f0fd92" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 4 + 5(n-1)</span></span> </div> </div> <div class="elementor-element elementor-element-a530773 elementor-invisible elementor-widget elementor-widget-heading" data-id="a530773" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 5n - 1</span></span> </div> </div> <div class="elementor-element elementor-element-043b863 elementor-invisible elementor-widget elementor-widget-heading" data-id="043b863" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">As <span class="katex-eq" data-katex-display="false">n \to \infty</span>:</span> </div> </div> <div class="elementor-element elementor-element-db77a3f elementor-invisible elementor-widget elementor-widget-heading" data-id="db77a3f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n \to \infty</span></span> </div> </div> <div class="elementor-element elementor-element-71580f2 elementor-invisible elementor-widget elementor-widget-heading" data-id="71580f2" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Important Conclusion</h3> </div> </div> <div class="elementor-element elementor-element-54a0590 elementor-invisible elementor-widget elementor-widget-heading" data-id="54a0590" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Arithmetic sequences:</span> </div> </div> <div class="elementor-element elementor-element-78e15b8 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-invisible elementor-widget elementor-widget-icon-list" data-id="78e15b8" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="icon-list.default"> <div class="elementor-widget-container"> <ul class="elementor-icon-list-items"> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Diverge if <span class="katex-eq" data-katex-display="false">d \neq 0</span></span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Converge only if <span class="katex-eq" data-katex-display="false">d = 0</span></span> </li> </ul> </div> </div> <div class="elementor-element elementor-element-2496ca8 elementor-invisible elementor-widget elementor-widget-heading" data-id="2496ca8" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">This is because linear growth does not "slow down.''</span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-1276b75d e-con-full e-flex e-con e-child" data-id="1276b75d" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-23d3783d elementor-invisible elementor-widget elementor-widget-heading" data-id="23d3783d" data-element_type="widget" data-e-type="widget" id="s3" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">Geometric Sequences — Exponential Behavior</h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-34f29258 e-con-full e-flex e-con e-child" data-id="34f29258" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-9a645c3 elementor-invisible elementor-widget elementor-widget-heading" data-id="9a645c3" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Conceptual Understanding</h3> </div> </div> <div class="elementor-element elementor-element-eada8ef elementor-invisible elementor-widget elementor-widget-heading" data-id="eada8ef" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Instead of adding a constant amount, geometric sequences multiply by a constant ratio.</span> </div> </div> <div class="elementor-element elementor-element-2f4b2ff elementor-invisible elementor-widget elementor-widget-heading" data-id="2f4b2ff" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\dfrac{a_{n+1}}{a_n} = r</span></span> </div> </div> <div class="elementor-element elementor-element-e3bc5d7 elementor-invisible elementor-widget elementor-widget-heading" data-id="e3bc5d7" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">This leads to exponential growth or decay.</span> </div> </div> <div class="elementor-element elementor-element-058ae0b elementor-invisible elementor-widget elementor-widget-heading" data-id="058ae0b" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Building the Formula</h3> </div> </div> <div class="elementor-element elementor-element-6031844 elementor-invisible elementor-widget elementor-widget-heading" data-id="6031844" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_1</span> </span> </div> </div> <div class="elementor-element elementor-element-72dba95 elementor-invisible elementor-widget elementor-widget-heading" data-id="72dba95" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_2 = a_1 r</span> </span> </div> </div> <div class="elementor-element elementor-element-fb893e1 elementor-invisible elementor-widget elementor-widget-heading" data-id="fb893e1" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_3 = a_1 r^2</span> </span> </div> </div> <div class="elementor-element elementor-element-5e11ad9 elementor-invisible elementor-widget elementor-widget-heading" data-id="5e11ad9" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">So: </span> </div> </div> <div class="elementor-element elementor-element-663923b elementor-invisible elementor-widget elementor-widget-heading" data-id="663923b" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = a_1 r^{n-1}</span></span> </div> </div> <div class="elementor-element elementor-element-54f84e6 elementor-invisible elementor-widget elementor-widget-heading" data-id="54f84e6" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Convergence Analysis</h3> </div> </div> <div class="elementor-element elementor-element-78fa989 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-invisible elementor-widget elementor-widget-icon-list" data-id="78fa989" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="icon-list.default"> <div class="elementor-widget-container"> <ul class="elementor-icon-list-items"> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">Everything depends on <span class="katex-eq" data-katex-display="false">|r|</span>.</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">If <span class="katex-eq" data-katex-display="false">|r| < 1</span>, the powers shrink toward 0.</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">If <span class="katex-eq" data-katex-display="false">|r| > 1</span>, powers grow without bound.</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">If <span class="katex-eq" data-katex-display="false">r = -1</span>, the sequence oscillates.</span> </li> </ul> </div> </div> <div class="elementor-element elementor-element-71cf306 elementor-invisible elementor-widget elementor-widget-heading" data-id="71cf306" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example </h3> </div> </div> <div class="elementor-element elementor-element-2a41836 elementor-invisible elementor-widget elementor-widget-heading" data-id="2a41836" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 8\left(\dfrac34\right)^{n-1}</span></span> </div> </div> <div class="elementor-element elementor-element-e7c2b19 elementor-invisible elementor-widget elementor-widget-heading" data-id="e7c2b19" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Since <span class="katex-eq" data-katex-display="false">|\dfrac34|<1</span>:</span> </div> </div> <div class="elementor-element elementor-element-19a8c1f elementor-invisible elementor-widget elementor-widget-heading" data-id="19a8c1f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} a_n = 0</span></span> </div> </div> <div class="elementor-element elementor-element-8709d26 elementor-invisible elementor-widget elementor-widget-heading" data-id="8709d26" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Exponential decay leads to convergence.</span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-9e50dfb e-con-full e-flex e-con e-child" data-id="9e50dfb" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-31f4e30 elementor-invisible elementor-widget elementor-widget-heading" data-id="31f4e30" data-element_type="widget" data-e-type="widget" id="s4" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">Limits of Sequences</h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-a749d3e e-con-full e-flex e-con e-child" data-id="a749d3e" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-b561df0 elementor-invisible elementor-widget elementor-widget-heading" data-id="b561df0" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">The limit of a sequence is defined as:</span> </div> </div> <div class="elementor-element elementor-element-1defb49 elementor-invisible elementor-widget elementor-widget-heading" data-id="1defb49" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} a_n = L</span></span> </div> </div> <div class="elementor-element elementor-element-34e862a elementor-invisible elementor-widget elementor-widget-heading" data-id="34e862a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">meaning the terms get arbitrarily close to <span class="katex-eq" data-katex-display="false">L</span>.</span> </div> </div> <div class="elementor-element elementor-element-e849eef elementor-invisible elementor-widget elementor-widget-heading" data-id="e849eef" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example — Rational Function</h3> </div> </div> <div class="elementor-element elementor-element-2ecb11a elementor-invisible elementor-widget elementor-widget-heading" data-id="2ecb11a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{4n^2 + 3}{2n^2 - 1}</span> </span> </div> </div> <div class="elementor-element elementor-element-eb6d457 elementor-invisible elementor-widget elementor-widget-heading" data-id="eb6d457" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Divide numerator and denominator by <span class="katex-eq" data-katex-display="false">n^2</span>: </span> </div> </div> <div class="elementor-element elementor-element-f58ab69 elementor-invisible elementor-widget elementor-widget-heading" data-id="f58ab69" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">= \dfrac{4 + \dfrac3{n^2}}{2 - \dfrac1{n^2}}</span> </span> </div> </div> <div class="elementor-element elementor-element-77b5b72 elementor-invisible elementor-widget elementor-widget-heading" data-id="77b5b72" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">As <span class="katex-eq" data-katex-display="false">n \to \infty</span>: </span> </div> </div> <div class="elementor-element elementor-element-f4aa76f elementor-invisible elementor-widget elementor-widget-heading" data-id="f4aa76f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} a_n = 2</span></span> </div> </div> <div class="elementor-element elementor-element-39d57aa elementor-invisible elementor-widget elementor-widget-heading" data-id="39d57aa" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Highest-degree terms dominate.</span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-e2c1664 e-con-full e-flex e-con e-child" data-id="e2c1664" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-d239128 elementor-invisible elementor-widget elementor-widget-heading" data-id="d239128" data-element_type="widget" data-e-type="widget" id="s5" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">The Sandwich (Squeeze) Theorem</h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-fc59bdd e-con-full e-flex e-con e-child" data-id="fc59bdd" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-15cda81 elementor-invisible elementor-widget elementor-widget-heading" data-id="15cda81" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Sometimes we cannot compute the limit directly.</span> </div> </div> <div class="elementor-element elementor-element-78b7b52 elementor-invisible elementor-widget elementor-widget-heading" data-id="78b7b52" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">The Idea</h3> </div> </div> <div class="elementor-element elementor-element-3717be0 elementor-invisible elementor-widget elementor-widget-heading" data-id="3717be0" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">If we trap a sequence between two simpler sequences that both approach the same limit, then the middle sequence must approach that limit too.</span> </div> </div> <div class="elementor-element elementor-element-096671d elementor-invisible elementor-widget elementor-widget-heading" data-id="096671d" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">If: <span class="katex-eq" data-katex-display="false">b_n \le a_n \le c_n</span> and <span class="katex-eq" data-katex-display="false">\lim b_n = \lim c_n = L</span>, then: <span class="katex-eq" data-katex-display="false">\lim a_n = L</span>.</span> </div> </div> <div class="elementor-element elementor-element-c08f5b7 elementor-invisible elementor-widget elementor-widget-heading" data-id="c08f5b7" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example</h3> </div> </div> <div class="elementor-element elementor-element-1d9e8ed elementor-invisible elementor-widget elementor-widget-heading" data-id="1d9e8ed" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{\sin n}{n}</span> </span> </div> </div> <div class="elementor-element elementor-element-ce364a9 elementor-invisible elementor-widget elementor-widget-heading" data-id="ce364a9" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Since:</span> </div> </div> <div class="elementor-element elementor-element-6a63598 elementor-invisible elementor-widget elementor-widget-heading" data-id="6a63598" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">-1 \le \sin n \le 1</span> </span> </div> </div> <div class="elementor-element elementor-element-f15364a elementor-invisible elementor-widget elementor-widget-heading" data-id="f15364a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Divide by <span class="katex-eq" data-katex-display="false">n</span>: </span> </div> </div> <div class="elementor-element elementor-element-4097999 elementor-invisible elementor-widget elementor-widget-heading" data-id="4097999" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">-\dfrac1n \le \frac{\sin n}{n} \le \dfrac1n</span></span> </div> </div> <div class="elementor-element elementor-element-ea7a8ec elementor-invisible elementor-widget elementor-widget-heading" data-id="ea7a8ec" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Both outer sequences approach 0.</span> </div> </div> <div class="elementor-element elementor-element-b423ed3 elementor-invisible elementor-widget elementor-widget-heading" data-id="b423ed3" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Therefore:</span> </div> </div> <div class="elementor-element elementor-element-786e625 elementor-invisible elementor-widget elementor-widget-heading" data-id="786e625" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} \dfrac{\sin n}{n} = 0</span></span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-eba6324 e-con-full e-flex e-con e-child" data-id="eba6324" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-7ec814e elementor-invisible elementor-widget elementor-widget-heading" data-id="7ec814e" data-element_type="widget" data-e-type="widget" id="s6" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">Absolute Value Theorem</h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-34c4f0c e-con-full e-flex e-con e-child" data-id="34c4f0c" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-19d09f4 elementor-invisible elementor-widget elementor-widget-heading" data-id="19d09f4" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Oscillating sequences can still converge.</span> </div> </div> <div class="elementor-element elementor-element-c8d5579 elementor-invisible elementor-widget elementor-widget-heading" data-id="c8d5579" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">The Principle</h3> </div> </div> <div class="elementor-element elementor-element-6c91538 elementor-invisible elementor-widget elementor-widget-heading" data-id="6c91538" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">If:</span> </div> </div> <div class="elementor-element elementor-element-e427f68 elementor-invisible elementor-widget elementor-widget-heading" data-id="e427f68" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} |a_n| = 0</span></span> </div> </div> <div class="elementor-element elementor-element-c7cde92 elementor-invisible elementor-widget elementor-widget-heading" data-id="c7cde92" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">then:</span> </div> </div> <div class="elementor-element elementor-element-b85c8ab elementor-invisible elementor-widget elementor-widget-heading" data-id="b85c8ab" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} a_n = 0.</span></span> </div> </div> <div class="elementor-element elementor-element-2cb4276 elementor-invisible elementor-widget elementor-widget-heading" data-id="2cb4276" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example</h3> </div> </div> <div class="elementor-element elementor-element-6bf67ba elementor-invisible elementor-widget elementor-widget-heading" data-id="6bf67ba" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{(-1)^n}{n}</span> </span> </div> </div> <div class="elementor-element elementor-element-e180fea elementor-invisible elementor-widget elementor-widget-heading" data-id="e180fea" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">The signs alternate.</span> </div> </div> <div class="elementor-element elementor-element-f49f110 elementor-invisible elementor-widget elementor-widget-heading" data-id="f49f110" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">But: </span> </div> </div> <div class="elementor-element elementor-element-c4902d7 elementor-invisible elementor-widget elementor-widget-heading" data-id="c4902d7" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">|a_n| = \dfrac1n \to 0</span> </span> </div> </div> <div class="elementor-element elementor-element-8cb7cd7 elementor-invisible elementor-widget elementor-widget-heading" data-id="8cb7cd7" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Therefore:</span> </div> </div> <div class="elementor-element elementor-element-6ab9047 elementor-invisible elementor-widget elementor-widget-heading" data-id="6ab9047" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n \to 0</span> </span> </div> </div> <div class="elementor-element elementor-element-3218fca elementor-invisible elementor-widget elementor-widget-heading" data-id="3218fca" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Oscillation does not prevent convergence if magnitude shrinks to 0.</span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-5f7b555 e-con-full e-flex e-con e-child" data-id="5f7b555" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-c918fae elementor-invisible elementor-widget elementor-widget-heading" data-id="c918fae" data-element_type="widget" data-e-type="widget" id="s7" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">Recursive Sequence — Deep Analysis Example</h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-3c54f19 e-con-full e-flex e-con e-child" data-id="3c54f19" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-a1b1989 elementor-invisible elementor-widget elementor-widget-heading" data-id="a1b1989" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_1 = 2</span></span> </div> </div> <div class="elementor-element elementor-element-0e6d989 elementor-invisible elementor-widget elementor-widget-heading" data-id="0e6d989" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_{n+1} = \dfrac12(a_n + 6)</span></span> </div> </div> <div class="elementor-element elementor-element-02c7fd9 elementor-invisible elementor-widget elementor-widget-heading" data-id="02c7fd9" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Assume limit <span class="katex-eq" data-katex-display="false">L</span> exists:</span> </div> </div> <div class="elementor-element elementor-element-1192346 elementor-invisible elementor-widget elementor-widget-heading" data-id="1192346" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">L = \dfrac12(L+6)</span></span> </div> </div> <div class="elementor-element elementor-element-13ca9ef elementor-invisible elementor-widget elementor-widget-heading" data-id="13ca9ef" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Solve:</span> </div> </div> <div class="elementor-element elementor-element-1a401f6 elementor-invisible elementor-widget elementor-widget-heading" data-id="1a401f6" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">2L = L+6</span></span> </div> </div> <div class="elementor-element elementor-element-10f611f elementor-invisible elementor-widget elementor-widget-heading" data-id="10f611f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">L=6</span></span> </div> </div> <div class="elementor-element elementor-element-11147f2 elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-invisible elementor-widget elementor-widget-icon-list" data-id="11147f2" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="icon-list.default"> <div class="elementor-widget-container"> <ul class="elementor-icon-list-items"> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">Then show:</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Sequence is increasing</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Sequence is bounded above by 6</span> </li> </ul> </div> </div> <div class="elementor-element elementor-element-0c3547c elementor-invisible elementor-widget elementor-widget-heading" data-id="0c3547c" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Therefore, it converges to 6.</span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-ac74496 e-con-full e-flex e-con e-child" data-id="ac74496" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-69b7193 elementor-invisible elementor-widget elementor-widget-heading" data-id="69b7193" data-element_type="widget" data-e-type="widget" id="s8" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">Monotonic and Bounded Sequences</h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-a9ba0fc e-con-full e-flex e-con e-child" data-id="a9ba0fc" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-cab06b0 elementor-invisible elementor-widget elementor-widget-heading" data-id="cab06b0" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Monotonic</h3> </div> </div> <div class="elementor-element elementor-element-542d929 elementor-invisible elementor-widget elementor-widget-heading" data-id="542d929" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">A sequence is monotonic if it always increases or always decreases.</span> </div> </div> <div class="elementor-element elementor-element-cf1b048 elementor-invisible elementor-widget elementor-widget-heading" data-id="cf1b048" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Bounded</h3> </div> </div> <div class="elementor-element elementor-element-62b7db4 elementor-invisible elementor-widget elementor-widget-heading" data-id="62b7db4" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">A sequence is bounded if it stays within fixed numbers.</span> </div> </div> <div class="elementor-element elementor-element-36e19d4 elementor-invisible elementor-widget elementor-widget-heading" data-id="36e19d4" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Monotone Convergence Theorem</h3> </div> </div> <div class="elementor-element elementor-element-f9e191c elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-invisible elementor-widget elementor-widget-icon-list" data-id="f9e191c" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="icon-list.default"> <div class="elementor-widget-container"> <ul class="elementor-icon-list-items"> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">If a sequence is:</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Monotonic</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Bounded</span> </li> </ul> </div> </div> <div class="elementor-element elementor-element-5204a6a elementor-invisible elementor-widget elementor-widget-heading" data-id="5204a6a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">then it must converge. </span> </div> </div> <div class="elementor-element elementor-element-805ad62 elementor-invisible elementor-widget elementor-widget-heading" data-id="805ad62" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">This is extremely important in recursive sequences.</span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-96347e1 e-con-full e-flex e-con e-child" data-id="96347e1" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-822b309 elementor-invisible elementor-widget elementor-widget-heading" data-id="822b309" data-element_type="widget" data-e-type="widget" id="s9" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">Worked Examples with Full Step-by-Step Solutions</h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-edb267e e-con-full e-flex e-con e-child" data-id="edb267e" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-fbe8612 elementor-invisible elementor-widget elementor-widget-heading" data-id="fbe8612" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example 1: Arithmetic Sequence — Explicit Formula</h3> </div> </div> <div class="elementor-element elementor-element-991e5cf elementor-invisible elementor-widget elementor-widget-heading" data-id="991e5cf" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Given: <span class="katex-eq" data-katex-display="false">a_1 = 7, \quad d = -3</span> </span> </div> </div> <div class="elementor-element elementor-element-ec58acf elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-invisible elementor-widget elementor-widget-icon-list" data-id="ec58acf" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="icon-list.default"> <div class="elementor-widget-container"> <ul class="elementor-icon-list-items"> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">Find:</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">1. An explicit formula for <span class="katex-eq" data-katex-display="false">a_n</span></span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">2. The 12th term</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">3. Whether the sequence converges</span> </li> </ul> </div> </div> <div class="elementor-element elementor-element-530990a elementor-invisible elementor-widget elementor-widget-heading" data-id="530990a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Solution:</h3> </div> </div> <div class="elementor-element elementor-element-ad80180 elementor-invisible elementor-widget elementor-widget-heading" data-id="ad80180" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 1: Use the explicit formula</span> </div> </div> <div class="elementor-element elementor-element-0504d09 elementor-invisible elementor-widget elementor-widget-heading" data-id="0504d09" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">For arithmetic sequences:</span> </div> </div> <div class="elementor-element elementor-element-97e70e1 elementor-invisible elementor-widget elementor-widget-heading" data-id="97e70e1" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = a_1 + (n-1)d</span></span> </div> </div> <div class="elementor-element elementor-element-0a15969 elementor-invisible elementor-widget elementor-widget-heading" data-id="0a15969" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Substitute values:</span> </div> </div> <div class="elementor-element elementor-element-3d217d0 elementor-invisible elementor-widget elementor-widget-heading" data-id="3d217d0" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 7 + (n-1)(-3)</span></span> </div> </div> <div class="elementor-element elementor-element-4769961 elementor-invisible elementor-widget elementor-widget-heading" data-id="4769961" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 7 - 3(n-1)</span></span> </div> </div> <div class="elementor-element elementor-element-361e262 elementor-invisible elementor-widget elementor-widget-heading" data-id="361e262" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 2: Simplify</span> </div> </div> <div class="elementor-element elementor-element-19b6616 elementor-invisible elementor-widget elementor-widget-heading" data-id="19b6616" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 7 - 3n + 3</span></span> </div> </div> <div class="elementor-element elementor-element-b16b9de elementor-invisible elementor-widget elementor-widget-heading" data-id="b16b9de" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 10 - 3n</span></span> </div> </div> <div class="elementor-element elementor-element-b4a60da elementor-invisible elementor-widget elementor-widget-heading" data-id="b4a60da" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 3: Find <span class="katex-eq" data-katex-display="false">a_{12}</span></span> </div> </div> <div class="elementor-element elementor-element-5d12d54 elementor-invisible elementor-widget elementor-widget-heading" data-id="5d12d54" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_{12} = 10 - 3(12)</span></span> </div> </div> <div class="elementor-element elementor-element-351ae3a elementor-invisible elementor-widget elementor-widget-heading" data-id="351ae3a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_{12} = 10 - 36</span></span> </div> </div> <div class="elementor-element elementor-element-d9ac604 elementor-invisible elementor-widget elementor-widget-heading" data-id="d9ac604" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_{12} = -26</span></span> </div> </div> <div class="elementor-element elementor-element-4ff5986 elementor-invisible elementor-widget elementor-widget-heading" data-id="4ff5986" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 4: Determine Convergence</span> </div> </div> <div class="elementor-element elementor-element-0258e9e elementor-invisible elementor-widget elementor-widget-heading" data-id="0258e9e" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">As <span class="katex-eq" data-katex-display="false">n \to \infty</span>:</span> </div> </div> <div class="elementor-element elementor-element-89f1809 elementor-invisible elementor-widget elementor-widget-heading" data-id="89f1809" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 10 - 3n \to -\infty</span></span> </div> </div> <div class="elementor-element elementor-element-93163fa elementor-invisible elementor-widget elementor-widget-heading" data-id="93163fa" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Conclusion:</b> The sequence diverges.</span> </div> </div> <div class="elementor-element elementor-element-fce36ec elementor-invisible elementor-widget elementor-widget-heading" data-id="fce36ec" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example 2: Geometric Sequence — Convergence Analysis</h3> </div> </div> <div class="elementor-element elementor-element-6c67acd elementor-invisible elementor-widget elementor-widget-heading" data-id="6c67acd" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Given: <span class="katex-eq" data-katex-display="false">a_1 = 9, \quad r = -\dfrac13</span></span> </div> </div> <div class="elementor-element elementor-element-e2625ae elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-invisible elementor-widget elementor-widget-icon-list" data-id="e2625ae" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="icon-list.default"> <div class="elementor-widget-container"> <ul class="elementor-icon-list-items"> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">Find:</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">1. Explicit formula</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">2. First four terms</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">3. Limit as <span class="katex-eq" data-katex-display="false">n \to \infty</span></span> </li> </ul> </div> </div> <div class="elementor-element elementor-element-68503a5 elementor-invisible elementor-widget elementor-widget-heading" data-id="68503a5" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Solution:</h3> </div> </div> <div class="elementor-element elementor-element-796eb1d elementor-invisible elementor-widget elementor-widget-heading" data-id="796eb1d" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 1: Formula</span> </div> </div> <div class="elementor-element elementor-element-1d1f0aa elementor-invisible elementor-widget elementor-widget-heading" data-id="1d1f0aa" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = a_1 r^{n-1}</span></span> </div> </div> <div class="elementor-element elementor-element-70e4c73 elementor-invisible elementor-widget elementor-widget-heading" data-id="70e4c73" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = 9\left(-\dfrac13\right)^{n-1}</span></span> </div> </div> <div class="elementor-element elementor-element-d72f4aa elementor-invisible elementor-widget elementor-widget-heading" data-id="d72f4aa" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 2: First Four Terms</span> </div> </div> <div class="elementor-element elementor-element-429a93f elementor-invisible elementor-widget elementor-widget-heading" data-id="429a93f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_1 = 9</span></span> </div> </div> <div class="elementor-element elementor-element-07b6577 elementor-invisible elementor-widget elementor-widget-heading" data-id="07b6577" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_2 = 9\left(-\dfrac13\right)</span></span> </div> </div> <div class="elementor-element elementor-element-de5aa16 elementor-invisible elementor-widget elementor-widget-heading" data-id="de5aa16" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_2 = -3</span></span> </div> </div> <div class="elementor-element elementor-element-9c18d9a elementor-invisible elementor-widget elementor-widget-heading" data-id="9c18d9a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_3 = -3\left(-\dfrac13\right)</span></span> </div> </div> <div class="elementor-element elementor-element-a31c4b2 elementor-invisible elementor-widget elementor-widget-heading" data-id="a31c4b2" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_3 = 1</span></span> </div> </div> <div class="elementor-element elementor-element-08a3dc1 elementor-invisible elementor-widget elementor-widget-heading" data-id="08a3dc1" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_4 = 1\left(-\dfrac13\right)</span></span> </div> </div> <div class="elementor-element elementor-element-36bcb8e elementor-invisible elementor-widget elementor-widget-heading" data-id="36bcb8e" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_4 = -\dfrac13</span></span> </div> </div> <div class="elementor-element elementor-element-75e295b elementor-invisible elementor-widget elementor-widget-heading" data-id="75e295b" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 3: Determine Limit</span> </div> </div> <div class="elementor-element elementor-element-c2e728f elementor-invisible elementor-widget elementor-widget-heading" data-id="c2e728f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Since: </span> </div> </div> <div class="elementor-element elementor-element-de25f41 elementor-invisible elementor-widget elementor-widget-heading" data-id="de25f41" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\left|-\dfrac13\right| < 1</span></span> </div> </div> <div class="elementor-element elementor-element-a5f92b8 elementor-invisible elementor-widget elementor-widget-heading" data-id="a5f92b8" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\left(-\dfrac13\right)^{n-1} \to 0</span></span> </div> </div> <div class="elementor-element elementor-element-145b686 elementor-invisible elementor-widget elementor-widget-heading" data-id="145b686" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Therefore: </span> </div> </div> <div class="elementor-element elementor-element-71f5430 elementor-invisible elementor-widget elementor-widget-heading" data-id="71f5430" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} a_n = 0</span></span> </div> </div> <div class="elementor-element elementor-element-da5163d elementor-invisible elementor-widget elementor-widget-heading" data-id="da5163d" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Conclusion:</b> Sequence converges to 0 (despite oscillation).</span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-7728d2f4 e-con-full e-flex e-con e-child" data-id="7728d2f4" data-element_type="container" data-e-type="container"> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-1cc3081b e-con-full e-flex e-con e-child" data-id="1cc3081b" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-bc4811e elementor-invisible elementor-widget elementor-widget-heading" data-id="bc4811e" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example 3: Rational Sequence — Limit</h3> </div> </div> <div class="elementor-element elementor-element-99de011 elementor-invisible elementor-widget elementor-widget-heading" data-id="99de011" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{5n^3 + 2n}{2n^3 - 7}</span></span> </div> </div> <div class="elementor-element elementor-element-e2ecc5a elementor-invisible elementor-widget elementor-widget-heading" data-id="e2ecc5a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Solution:</h3> </div> </div> <div class="elementor-element elementor-element-f24ab53 elementor-invisible elementor-widget elementor-widget-heading" data-id="f24ab53" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 1: Identify Highest Power</span> </div> </div> <div class="elementor-element elementor-element-226c66f elementor-invisible elementor-widget elementor-widget-heading" data-id="226c66f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Highest power in numerator and denominator is <span class="katex-eq" data-katex-display="false">n^3</span>.</span> </div> </div> <div class="elementor-element elementor-element-e596ecc elementor-invisible elementor-widget elementor-widget-heading" data-id="e596ecc" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 2: Divide by <span class="katex-eq" data-katex-display="false">n^3</span></span> </div> </div> <div class="elementor-element elementor-element-32a3069 elementor-invisible elementor-widget elementor-widget-heading" data-id="32a3069" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{5 + \dfrac{2}{n^2}} {2 - \dfrac{7}{n^3}} </span></span> </div> </div> <div class="elementor-element elementor-element-a16a9fa elementor-invisible elementor-widget elementor-widget-heading" data-id="a16a9fa" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 3: Take Limit</span> </div> </div> <div class="elementor-element elementor-element-0559d80 elementor-invisible elementor-widget elementor-widget-heading" data-id="0559d80" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">As <span class="katex-eq" data-katex-display="false">n \to \infty</span>:</span> </div> </div> <div class="elementor-element elementor-element-e332438 elementor-invisible elementor-widget elementor-widget-heading" data-id="e332438" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\dfrac{2}{n^2} \to 0</span></span> </div> </div> <div class="elementor-element elementor-element-a51ee1d elementor-invisible elementor-widget elementor-widget-heading" data-id="a51ee1d" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\dfrac{7}{n^3} \to 0</span></span> </div> </div> <div class="elementor-element elementor-element-a578b44 elementor-invisible elementor-widget elementor-widget-heading" data-id="a578b44" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">So:</span> </div> </div> <div class="elementor-element elementor-element-e5f5280 elementor-invisible elementor-widget elementor-widget-heading" data-id="e5f5280" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} a_n = \dfrac{5}{2}</span></span> </div> </div> <div class="elementor-element elementor-element-0eea985 elementor-invisible elementor-widget elementor-widget-heading" data-id="0eea985" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example 4: Sandwich Theorem Application</h3> </div> </div> <div class="elementor-element elementor-element-35f3c96 elementor-invisible elementor-widget elementor-widget-heading" data-id="35f3c96" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{\cos(3n)}{n}</span></span> </div> </div> <div class="elementor-element elementor-element-c164150 elementor-invisible elementor-widget elementor-widget-heading" data-id="c164150" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Solution:</h3> </div> </div> <div class="elementor-element elementor-element-bc0d3f8 elementor-invisible elementor-widget elementor-widget-heading" data-id="bc0d3f8" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 1: Use Trigonometric Bounds</span> </div> </div> <div class="elementor-element elementor-element-aa35131 elementor-invisible elementor-widget elementor-widget-heading" data-id="aa35131" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">We know:</span> </div> </div> <div class="elementor-element elementor-element-bd794db elementor-invisible elementor-widget elementor-widget-heading" data-id="bd794db" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">-1 \le \cos(3n) \le 1</span></span> </div> </div> <div class="elementor-element elementor-element-9713351 elementor-invisible elementor-widget elementor-widget-heading" data-id="9713351" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 2: Divide by <span class="katex-eq" data-katex-display="false">n[katex]</span> </div> </div> <div class="elementor-element elementor-element-5a753eb elementor-invisible elementor-widget elementor-widget-heading" data-id="5a753eb" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">[katex]-\dfrac1n \le \dfrac{\cos(3n)}{n} \le \dfrac1n</span></span> </div> </div> <div class="elementor-element elementor-element-8fc9b85 elementor-invisible elementor-widget elementor-widget-heading" data-id="8fc9b85" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 3: Take Limits of Bounds</span> </div> </div> <div class="elementor-element elementor-element-af90e17 elementor-invisible elementor-widget elementor-widget-heading" data-id="af90e17" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">-\dfrac1n \to 0</span></span> </div> </div> <div class="elementor-element elementor-element-164eeb3 elementor-invisible elementor-widget elementor-widget-heading" data-id="164eeb3" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\dfrac1n \to 0</span></span> </div> </div> <div class="elementor-element elementor-element-75bbd1a elementor-invisible elementor-widget elementor-widget-heading" data-id="75bbd1a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 4: Apply Sandwich Theorem</span> </div> </div> <div class="elementor-element elementor-element-367132d elementor-invisible elementor-widget elementor-widget-heading" data-id="367132d" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim_{n\to\infty} \dfrac{\cos(3n)}{n} = 0</span></span> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-7b644a4 e-con-full e-flex e-con e-child" data-id="7b644a4" data-element_type="container" data-e-type="container"> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-aea04f0 e-con-full e-flex e-con e-child" data-id="aea04f0" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-e23e467 elementor-invisible elementor-widget elementor-widget-heading" data-id="e23e467" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example 5: Absolute Value Theorem</h3> </div> </div> <div class="elementor-element elementor-element-207627a elementor-invisible elementor-widget elementor-widget-heading" data-id="207627a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{(-1)^n \sqrt{n}}{n}</span></span> </div> </div> <div class="elementor-element elementor-element-5135cfd elementor-invisible elementor-widget elementor-widget-heading" data-id="5135cfd" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Solution:</h3> </div> </div> <div class="elementor-element elementor-element-b34e82f elementor-invisible elementor-widget elementor-widget-heading" data-id="b34e82f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 1: Simplify</span> </div> </div> <div class="elementor-element elementor-element-c279c4b elementor-invisible elementor-widget elementor-widget-heading" data-id="c279c4b" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n = \dfrac{(-1)^n}{\sqrt{n}}</span>.</span> </div> </div> <div class="elementor-element elementor-element-adff11c elementor-invisible elementor-widget elementor-widget-heading" data-id="adff11c" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 2: Take Absolute Value</span> </div> </div> <div class="elementor-element elementor-element-da2d525 elementor-invisible elementor-widget elementor-widget-heading" data-id="da2d525" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">|a_n| = \dfrac{1}{\sqrt{n}} </span></span> </div> </div> <div class="elementor-element elementor-element-1f952e1 elementor-invisible elementor-widget elementor-widget-heading" data-id="1f952e1" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 3: Take Limit</span> </div> </div> <div class="elementor-element elementor-element-b6f3411 elementor-invisible elementor-widget elementor-widget-heading" data-id="b6f3411" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"> <span class="katex-eq" data-katex-display="false">\dfrac{1}{\sqrt{n}} \to 0</span></span> </div> </div> <div class="elementor-element elementor-element-7f5f69a elementor-invisible elementor-widget elementor-widget-heading" data-id="7f5f69a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 4: Apply Absolute Value Theorem</span> </div> </div> <div class="elementor-element elementor-element-413a1dd elementor-invisible elementor-widget elementor-widget-heading" data-id="413a1dd" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Since <span class="katex-eq" data-katex-display="false">|a_n| \to 0</span>,</span> </div> </div> <div class="elementor-element elementor-element-42af292 elementor-invisible elementor-widget elementor-widget-heading" data-id="42af292" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_n \to 0</span></span> </div> </div> <div class="elementor-element elementor-element-aaa9eac elementor-invisible elementor-widget elementor-widget-heading" data-id="aaa9eac" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Example 6: Recursive Sequence — Full Justification</h3> </div> </div> <div class="elementor-element elementor-element-0a92e42 elementor-invisible elementor-widget elementor-widget-heading" data-id="0a92e42" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_1 = 4</span></span> </div> </div> <div class="elementor-element elementor-element-00ad39f elementor-invisible elementor-widget elementor-widget-heading" data-id="00ad39f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_{n+1} = \dfrac12(a_n + 8)</span></span> </div> </div> <div class="elementor-element elementor-element-5b80b5f elementor-invisible elementor-widget elementor-widget-heading" data-id="5b80b5f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h3 class="elementor-heading-title elementor-size-default">Solution:</h3> </div> </div> <div class="elementor-element elementor-element-0d9a227 elementor-invisible elementor-widget elementor-widget-heading" data-id="0d9a227" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 1: Assume Limit Exists</span> </div> </div> <div class="elementor-element elementor-element-f46ff06 elementor-invisible elementor-widget elementor-widget-heading" data-id="f46ff06" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Let:</span> </div> </div> <div class="elementor-element elementor-element-9add686 elementor-invisible elementor-widget elementor-widget-heading" data-id="9add686" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim a_n = L</span></span> </div> </div> <div class="elementor-element elementor-element-6cbce06 elementor-invisible elementor-widget elementor-widget-heading" data-id="6cbce06" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 2: Substitute into Recursion</span> </div> </div> <div class="elementor-element elementor-element-1615666 elementor-invisible elementor-widget elementor-widget-heading" data-id="1615666" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">L = \dfrac12(L+8)</span></span> </div> </div> <div class="elementor-element elementor-element-5086e8a elementor-invisible elementor-widget elementor-widget-heading" data-id="5086e8a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">2L = L + 8</span></span> </div> </div> <div class="elementor-element elementor-element-f0f092f elementor-invisible elementor-widget elementor-widget-heading" data-id="f0f092f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">L = 8</span></span> </div> </div> <div class="elementor-element elementor-element-5c40646 elementor-invisible elementor-widget elementor-widget-heading" data-id="5c40646" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 3: Show Boundedness</span> </div> </div> <div class="elementor-element elementor-element-9956315 elementor-invisible elementor-widget elementor-widget-heading" data-id="9956315" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Assume <span class="katex-eq" data-katex-display="false">a_n < 8</span>.</span> </div> </div> <div class="elementor-element elementor-element-7ed5101 elementor-invisible elementor-widget elementor-widget-heading" data-id="7ed5101" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Then:</span> </div> </div> <div class="elementor-element elementor-element-e7ec712 elementor-invisible elementor-widget elementor-widget-heading" data-id="e7ec712" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_{n+1} = \dfrac12(a_n + 8) < 8</span></span> </div> </div> <div class="elementor-element elementor-element-aadae70 elementor-invisible elementor-widget elementor-widget-heading" data-id="aadae70" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">So sequence is bounded above by 8.</span> </div> </div> <div class="elementor-element elementor-element-352c67d elementor-invisible elementor-widget elementor-widget-heading" data-id="352c67d" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Step 4: Show Monotonicity</span> </div> </div> <div class="elementor-element elementor-element-cdd95ef elementor-invisible elementor-widget elementor-widget-heading" data-id="cdd95ef" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">a_{n+1} - a_n = \dfrac12(a_n+8) - a_n</span></span> </div> </div> <div class="elementor-element elementor-element-6239e10 elementor-invisible elementor-widget elementor-widget-heading" data-id="6239e10" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">= \dfrac12a_n + 4 - a_n</span></span> </div> </div> <div class="elementor-element elementor-element-ca5644a elementor-invisible elementor-widget elementor-widget-heading" data-id="ca5644a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">= 4 - \dfrac12 a_n</span></span> </div> </div> <div class="elementor-element elementor-element-840d671 elementor-invisible elementor-widget elementor-widget-heading" data-id="840d671" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">If <span class="katex-eq" data-katex-display="false">a_n < 8</span>, then:</span> </div> </div> <div class="elementor-element elementor-element-273992f elementor-invisible elementor-widget elementor-widget-heading" data-id="273992f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">4 - \dfrac12 a_n > 0</span></span> </div> </div> <div class="elementor-element elementor-element-3a1004a elementor-invisible elementor-widget elementor-widget-heading" data-id="3a1004a" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Thus sequence is increasing.</span> </div> </div> <div class="elementor-element elementor-element-2524154 elementor-invisible elementor-widget elementor-widget-heading" data-id="2524154" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><b>Final Conclusion</span> </div> </div> <div class="elementor-element elementor-element-10ce17c elementor-icon-list--layout-traditional elementor-list-item-link-full_width elementor-invisible elementor-widget elementor-widget-icon-list" data-id="10ce17c" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="icon-list.default"> <div class="elementor-widget-container"> <ul class="elementor-icon-list-items"> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-text">Sequence is:</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Increasing</span> </li> <li class="elementor-icon-list-item"> <span class="elementor-icon-list-icon"> <svg aria-hidden="true" class="e-font-icon-svg e-fas-check" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg"><path d="M173.898 439.404l-166.4-166.4c-9.997-9.997-9.997-26.206 0-36.204l36.203-36.204c9.997-9.998 26.207-9.998 36.204 0L192 312.69 432.095 72.596c9.997-9.997 26.207-9.997 36.204 0l36.203 36.204c9.997 9.997 9.997 26.206 0 36.204l-294.4 294.401c-9.998 9.997-26.207 9.997-36.204-.001z"></path></svg> </span> <span class="elementor-icon-list-text">Bounded above by 8</span> </li> </ul> </div> </div> <div class="elementor-element elementor-element-d01b45f elementor-invisible elementor-widget elementor-widget-heading" data-id="d01b45f" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">By Monotone Convergence Theorem:</span> </div> </div> <div class="elementor-element elementor-element-b2aee1c elementor-invisible elementor-widget elementor-widget-heading" data-id="b2aee1c" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default"><span class="katex-eq" data-katex-display="false">\lim a_n = 8</span></span> </div> </div> </div> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-8c63d3a e-con-full e-flex e-con e-child" data-id="8c63d3a" data-element_type="container" data-e-type="container" id="s7"> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-4c50c660 e-con-full e-flex e-con e-child" data-id="4c50c660" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-22d74931 elementor-invisible elementor-widget elementor-widget-heading" data-id="22d74931" data-element_type="widget" data-e-type="widget" id="s10" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <h2 class="elementor-heading-title elementor-size-default">Frequently Asked Questions </h2> </div> </div> <div data-particle_enable="false" data-particle-mobile-disabled="false" class="elementor-element elementor-element-42cdaf6c e-con-full e-flex e-con e-child" data-id="42cdaf6c" data-element_type="container" data-e-type="container"> <div class="elementor-element elementor-element-01e2827 elementor-widget elementor-widget-n-accordion" data-id="01e2827" data-element_type="widget" data-e-type="widget" data-settings="{"default_state":"all_collapsed","max_items_expended":"one","n_accordion_animation_duration":{"unit":"ms","size":400,"sizes":[]}}" data-widget_type="nested-accordion.default"> <div class="elementor-widget-container"> <div class="e-n-accordion" aria-label="Accordion. Open links with Enter or Space, close with Escape, and navigate with Arrow Keys"> <details id="e-n-accordion-item-1970" class="e-n-accordion-item" > <summary class="e-n-accordion-item-title" data-accordion-index="1" tabindex="0" aria-expanded="false" aria-controls="e-n-accordion-item-1970" > <span class='e-n-accordion-item-title-header'><div class="e-n-accordion-item-title-text"> Q1: Why do arithmetic sequences usually diverge? </div></span> <span class='e-n-accordion-item-title-icon'> <span class='e-opened' ><svg aria-hidden="true" class="e-font-icon-svg e-fas-chevron-down" viewBox="0 0 448 512" xmlns="http://www.w3.org/2000/svg"><path d="M207.029 381.476L12.686 187.132c-9.373-9.373-9.373-24.569 0-33.941l22.667-22.667c9.357-9.357 24.522-9.375 33.901-.04L224 284.505l154.745-154.021c9.379-9.335 24.544-9.317 33.901.04l22.667 22.667c9.373 9.373 9.373 24.569 0 33.941L240.971 381.476c-9.373 9.372-24.569 9.372-33.942 0z"></path></svg></span> <span class='e-closed'><svg aria-hidden="true" class="e-font-icon-svg e-fas-chevron-up" viewBox="0 0 448 512" xmlns="http://www.w3.org/2000/svg"><path d="M240.971 130.524l194.343 194.343c9.373 9.373 9.373 24.569 0 33.941l-22.667 22.667c-9.357 9.357-24.522 9.375-33.901.04L224 227.495 69.255 381.516c-9.379 9.335-24.544 9.317-33.901-.04l-22.667-22.667c-9.373-9.373-9.373-24.569 0-33.941L207.03 130.525c9.372-9.373 24.568-9.373 33.941-.001z"></path></svg></span> </span> </summary> <div data-particle_enable="false" data-particle-mobile-disabled="false" role="region" aria-labelledby="e-n-accordion-item-1970" class="elementor-element elementor-element-e61ad4b e-con-full e-flex e-con e-child" data-id="e61ad4b" data-element_type="container" data-e-type="container"> <div data-particle_enable="false" data-particle-mobile-disabled="false" role="region" aria-labelledby="e-n-accordion-item-1970" class="elementor-element elementor-element-fe45203 e-flex e-con-boxed e-con e-child" data-id="fe45203" data-element_type="container" data-e-type="container"> <div class="e-con-inner"> <div class="elementor-element elementor-element-d0f0ab9 elementor-invisible elementor-widget elementor-widget-heading" data-id="d0f0ab9" data-element_type="widget" data-e-type="widget" data-settings="{"_animation":"fadeInUp"}" data-widget_type="heading.default"> <div class="elementor-widget-container"> <span class="elementor-heading-title elementor-size-default">Because linear growth continues without slowing down.</span> </div> </div> </div> </div> </div> </details> <details id="e-n-accordion-item-1971" class="e-n-accordion-item" > <summary class="e-n-accordion-item-title" data-accordion-index="2" tabindex="-1" aria-expanded="false" aria-controls="e-n-accordion-item-1971" > <span class='e-n-accordion-item-title-header'><div class="e-n-accordion-item-title-text"> Q2: Why does [katex]|r|<1 guarantee convergence in geometric sequences?
Because repeated multiplication shrinks the terms toward 0.
It allows us to evaluate limits that cannot be computed directly.
It measures size regardless of sign.
Because series are sums of sequence terms.

Final Takeaway

To master AP Calculus BC sequences, you must understand:
At mathaversity we help students do well in AP Calculus BC by giving them personalized lessons, practice sessions, and tips for taking tests. Make an appointment for your free demo today and improve your AP Calculus skills!