lkarch.org/tools/mathisfun/www.mathsisfun.com/algebra/rational-expression-operations.html
Lucas Kent e39465ad2f Changes to be committed:
new file:   Files/flashplayer_32_sa.exe
	new file:   favicon.ico
	new file:   globe.gif
	new file:   imgs/download.png
	new file:   imgs/zuck.jpg
	new file:   index.html
	new file:   other.ico
	new file:   script.js
	new file:   site.webmanifest
	new file:   sitemap.html
	new file:   styles/backround.css
	new file:   styles/border.css
	new file:   styles/fonts/Titillium_Web/OFL.txt
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-Black.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-Bold.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-BoldItalic.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-ExtraLight.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-ExtraLightItalic.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-Italic.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-Light.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-LightItalic.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-Regular.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-SemiBold.ttf
	new file:   styles/fonts/Titillium_Web/TitilliumWeb-SemiBoldItalic.ttf
	new file:   styles/fonts/webfontkit-20221027-163353/generator_config.txt
	new file:   styles/fonts/webfontkit-20221027-163353/specimen_files/grid_12-825-55-15.css
	new file:   styles/fonts/webfontkit-20221027-163353/specimen_files/specimen_stylesheet.css
	new file:   styles/fonts/webfontkit-20221027-163353/stylesheet.css
	new file:   styles/fonts/webfontkit-20221027-163353/titilliumweb-extralight-demo.html
	new file:   styles/fonts/webfontkit-20221027-163353/titilliumweb-extralight-webfont.woff
	new file:   styles/fonts/webfontkit-20221027-163353/titilliumweb-extralight-webfont.woff2
	new file:   styles/fonts/webfontkit-20221027-165950/generator_config.txt
	new file:   styles/fonts/webfontkit-20221027-165950/specimen_files/grid_12-825-55-15.css
	new file:   styles/fonts/webfontkit-20221027-165950/specimen_files/specimen_stylesheet.css
	new file:   styles/fonts/webfontkit-20221027-165950/stylesheet.css
	new file:   styles/fonts/webfontkit-20221027-165950/titilliumweb-bold-demo.html
	new file:   styles/fonts/webfontkit-20221027-165950/titilliumweb-bold-webfont.woff
	new file:   styles/fonts/webfontkit-20221027-165950/titilliumweb-bold-webfont.woff2
	new file:   styles/style.css
	new file:   tools/2048/.gitignore
	new file:   tools/2048/.jshintrc
	new file:   tools/2048/CONTRIBUTING.md
	new file:   tools/2048/LICENSE.txt
	new file:   tools/2048/README.md
	new file:   tools/2048/Rakefile
	new file:   tools/2048/favicon.ico
	new file:   tools/2048/index.html
	new file:   tools/2048/js/animframe_polyfill.js
	new file:   tools/2048/js/application.js
	new file:   tools/2048/js/bind_polyfill.js
	new file:   tools/2048/js/classlist_polyfill.js
	new file:   tools/2048/js/game_manager.js
	new file:   tools/2048/js/grid.js
	new file:   tools/2048/js/html_actuator.js
	new file:   tools/2048/js/keyboard_input_manager.js
	new file:   tools/2048/js/local_storage_manager.js
	new file:   tools/2048/js/tile.js
    new file:   tools/2048/meta/apple-touch-icon.png
	new file:   tools/webretro/cores/neocd_libretro.js
	new file:   tools/webretro/cores/neocd_libretro.wasm
	new file:   tools/webretro/cores/nestopia_libretro.js
	new file:   tools/webretro/cores/nestopia_libretro.wasm
	new file:   tools/webretro/cores/o2em_libretro.js
	new file:   tools/webretro/cores/o2em_libretro.wasm
	new file:   tools/webretro/cores/opera_libretro.js
	new file:   tools/webretro/cores/opera_libretro.wasm
2022-11-02 08:40:01 -04:00

168 lines
9.4 KiB
HTML

<!doctype html>
<html lang="en"><!-- #BeginTemplate "/Templates/Advanced.dwt" --><!-- DW6 -->
<!-- Mirrored from www.mathsisfun.com/algebra/rational-expression-operations.html by HTTrack Website Copier/3.x [XR&CO'2014], Sat, 29 Oct 2022 01:02:29 GMT -->
<head>
<!-- #BeginEditable "doctitle" -->
<title>Using Rational Expressions</title>
<!-- #EndEditable -->
<meta name="keywords" content="math, maths, mathematics, school, homework, education" />
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<meta name="viewport" content="width=device-width; initial-scale=1.0; user-scalable=true;" />
<meta name="HandheldFriendly" content="true"/>
<meta http-equiv="pics-label" content='(PICS-1.1 "http://www.classify.org/safesurf/" L gen true for "http://www.mathsisfun.com" r (SS~~000 1))' />
<link rel="stylesheet" type="text/css" href="../style3.css" />
<script src="../main3.js" type="text/javascript"></script>
</head>
<body id="bodybg" class="adv">
<div class="bg">
<div id="stt"></div>
<div id="hdr"></div>
<div id="logo"><a href="../index.html"><img src="../images/style/logo.svg" alt="Math is Fun" /></a></div>
<div id="advText">Advanced</div>
<div id="gtran"><script type="text/javascript">document.write(getTrans());</script></div>
<div id="gplus"><script type="text/javascript">document.write(getGPlus());</script></div>
<div id="adTopOuter" class="centerfull noprint">
<div id="adTop">
<script type="text/javascript">document.write(getAdTop());</script>
</div>
</div>
<div id="adHide">
<div id="showAds1"><a href="javascript:showAds()">Show Ads</a></div>
<div id="hideAds1"><a href="javascript:hideAds()">Hide Ads</a><br>
<a href="../about-ads.html">About Ads</a></div>
</div>
<div id="menuWide" class="menu">
<script type="text/javascript">document.write(getMenu(0));</script>
</div>
<div id="linkto">
<div id="linktort"><script type="text/javascript">document.write(getLinks());</script></div>
</div>
<div id="search" role="search"><script type="text/javascript">document.write(getSearch());</script></div>
<div id="menuSlim" class="menu">
<script type="text/javascript">document.write(getMenu(1));</script>
</div>
<div id="menuTiny" class="menu">
<script type="text/javascript">document.write(getMenu(2));</script>
</div>
<div id="extra"></div>
</div>
<div id="content" role="main"><!-- #BeginEditable "Body" --> <h1 align="center">Using Rational Expressions</h1>
<p>A <a href="rational-expression.html">Rational Expression</a> is the ratio of two <a href="polynomials.html">polynomials</a>:</p>
<p align="center"><img src="images/rational-expression.svg" alt="Rational Expression" /></p>
<h2>Using Rational Expressions</h2>
<p>Using Rational Expressions is very similar to <a href="rational-numbers-operations.html">Using Rational Numbers</a> (you may like to read that first).</p>
<h2>Adding Rational Expressions</h2>
<p>The easiest way to add Rational Expressions is to use the <a href="../numbers/common-denominator.html">common denominator</a> method:</p>
<div class="beach">
<table border="0" align="center">
<tr>
<td><img src="../numbers/images/common-factor-formula.gif" alt="common-factor-formula" width="315" height="60" /></td>
</tr>
</table>
</div>
<p>Like in this example:</p>
<div class="example">
<h3>Example: </h3><p class="center large"><span class="intbl"><em>2</em><strong>x&minus;2</strong></span> + <span class="intbl"><em>3</em><strong>x+1</strong></span>&nbsp; = &nbsp;<span class="intbl"><em>2 &times; (x+1) + (x&minus;2) &times; 3</em><strong>(x&minus;2) &times; (x+1)</strong></span></p>
<div class="example2"></div>
<p>And then simplify to:</p>
<p class="center large">= &nbsp;<span class="intbl">
<em>2x+2 + 3x&minus;6</em>
<strong>x<sup>2</sup>+x&minus;2x&minus;2</strong>
</span></p>
<p class="center large">= &nbsp;<span class="intbl">
<em>5x&minus;4</em>
<strong>x<sup>2</sup>&minus;x&minus;2</strong>
</span></p>
</div>
<h2>Subtracting Rational Expressions</h2>
<p>Subtracting is just like Adding:</p>
<div class="example">
<h3>Example: </h3>
<p class="center large"><span class="intbl">
<em>2</em>
<strong>x&minus;2</strong>
</span> &minus; <span class="intbl">
<em>3</em>
<strong>x+1</strong>
</span>&nbsp; = &nbsp;<span class="intbl">
<em>2 &times; (x+1) &minus; (x&minus;2) &times; 3</em>
<strong>(x&minus;2) &times; (x+1)</strong>
</span></p>
<div class="example2"></div>
<p>And then simplify to:</p>
<p class="center large">= &nbsp;<span class="intbl">
<em>2x+2 &minus; (3x&minus;6)</em>
<strong>x<sup>2</sup>+x&minus;2x&minus;2</strong>
</span></p>
<p class="center large">= &nbsp;<span class="intbl">
<em>&minus;x + 8</em>
<strong>x<sup>2</sup>&minus;x&minus;2</strong>
</span></p>
</div>
<h2>Multiplication</h2>
<p>To multiply two Rational Expressions, just multiply the tops and bottoms separately, like this:</p>
<div class="example">
<h3>Example: </h3>
<p class="center large"><span class="intbl"><em>2</em><strong>x&minus;2</strong></span>&nbsp; &times; &nbsp;<span class="intbl"><em>3</em><strong>x+1</strong></span>&nbsp; = &nbsp;<span class="intbl"><em>2&times;3</em><strong>(x&minus;2)(x+1)</strong></span></p>
<p>And then simplify to:</p>
<p class="center large">&nbsp; = &nbsp;<span class="intbl"><em>6</em><strong>x<sup>2</sup>&minus;x&minus;2</strong></span></p>
</div>
<h2>Division</h2>
<p>To divide two Rational Expressions, first flip the second expression over (make it a reciprocal) and then do a multiply like above:</p>
<div class="example">
<h3>Example: </h3>
<p>First flip the second one over and make it a multiply:</p><p class="center large"><span class="intbl"><em>2</em><strong>x<span class="large">&minus;</span>2</strong>
</span>&nbsp; / &nbsp;<span class="intbl">
<em>3</em><strong>x+1</strong></span><span class="large">&nbsp; = &nbsp;</span><span class="intbl"><em>2</em><strong>x<span class="large">&minus;</span>2</strong></span><span class="large">&nbsp; &times; &nbsp;</span><span class="intbl"><em>x+1</em><strong>3</strong></span></p>
<p>Then do the multiply:</p>
<p class="center large"><span class="intbl">
<em>2</em>
<strong>x<span class="large">&minus;</span>2</strong>
</span><span class="large">&nbsp; &times; &nbsp;</span><span class="intbl"><em>x+1</em><strong>3</strong></span>&nbsp; = &nbsp;<span class="intbl"><em>2(x+1)</em><strong>3(x<span class="large">&minus;</span>2)</strong></span></p>
</div>
<h2>Simplifying</h2>
<p>When simplifying a rational function be careful to respect where the lower polynomial is equal to zero</p>
<div class="example">
<h3>Example: </h3>
<p class="center large"><span class="intbl"><em>x<sup>2</sup>&minus;1</em><strong>x+1</strong></span> is undefined when x=&minus;1</p>
<p align="center">Its <a href="../sets/domain-range-codomain.html">Domain</a> (the values that can go into the expression) does not include &minus;1</p>
<p>&nbsp;</p>
<p>Now, we can factor <span class="larger">x<sup>2</sup>&minus;1</span> into <span class="larger">(x&minus;1)(x+1)</span> so we get:</p>
<p class="center large"><span class="intbl"><em>(x&minus;1)(x+1)</em><strong>(x+1)</strong></span></p>
<p>It is now tempting to cancel <span class="large">(x+1)</span> from top and bottom to produce:</p>
<p align="center"> <span class="large">x &minus; 1</span></p>
<p align="center">Its Domain now <b>does</b> include &minus;1</p>
<p>But it is now a different function because it has a different Domain.</p>
</div>
<p>&nbsp;</p>
<div class="questions">
<script type="text/javascript">getQ(474, 475, 476, 477, 2288, 2289, 2290, 2291, 1120, 1121);</script>&nbsp;
</div>
<div class="related"> <a href="polynomials.html">Polynomials</a> <a href="index.html">Algebra Index</a></div><!-- #EndEditable --></div>
<div id="adend" class="centerfull noprint">
<script type="text/javascript">document.write(getAdEnd());</script>
</div>
<div id="footer" class="centerfull noprint">
<script type="text/javascript">document.write(getFooter());</script>
</div>
<div id="copyrt">
Copyright &copy; 2017 MathsIsFun.com
</div>
<script type="text/javascript">document.write(getBodyEnd());</script>
</body>
<!-- #EndTemplate -->
<!-- Mirrored from www.mathsisfun.com/algebra/rational-expression-operations.html by HTTrack Website Copier/3.x [XR&CO'2014], Sat, 29 Oct 2022 01:02:29 GMT -->
</html>