<?xml version='1.0'?> <?xml-stylesheet type='text/xsl' href='pmathml.xsl'?> <html xmlns='http://www.w3.org/1999/xhtml'> <head> <title>Arccosine Function Forward Taylor Polynomial Theory</title> <meta name="description" id="description" content="Arccosine Function Forward Taylor Polynomial Theory"/> <meta name="keywords" id="keywords" content=" acos forward theory "/> <style type='text/css'> body { color : black } body { background-color : white } A:link { color : blue } A:visited { color : purple } A:active { color : purple } </style> <script type='text/javascript' language='JavaScript' src='_acosforward_xml.js'> </script> </head> <body> <table><tr> <td> <a href="http://www.coin-or.org/CppAD/" target="_top"><img border="0" src="_image.gif"/></a> </td> <td><a href="asinforward.xml" target="_top">Prev</a> </td><td><a href="reversetheory.xml" target="_top">Next</a> </td><td> <select onchange='choose_across0(this)'> <option>Index-></option> <option>contents</option> <option>reference</option> <option>index</option> <option>search</option> <option>external</option> </select> </td> <td> <select onchange='choose_up0(this)'> <option>Up-></option> <option>CppAD</option> <option>Appendix</option> <option>Theory</option> <option>ForwardTheory</option> <option>AcosForward</option> </select> </td> <td> <select onchange='choose_down3(this)'> <option>Appendix-></option> <option>Faq</option> <option>speed</option> <option>Theory</option> <option>glossary</option> <option>Bib</option> <option>Bugs</option> <option>WishList</option> <option>whats_new</option> <option>include_deprecated</option> <option>License</option> </select> </td> <td> <select onchange='choose_down2(this)'> <option>Theory-></option> <option>ForwardTheory</option> <option>ReverseTheory</option> <option>reverse_identity</option> </select> </td> <td> <select onchange='choose_down1(this)'> <option>ForwardTheory-></option> <option>ExpForward</option> <option>LogForward</option> <option>SqrtForward</option> <option>SinCosForward</option> <option>AtanForward</option> <option>AsinForward</option> <option>AcosForward</option> </select> </td> <td>AcosForward</td> <td>Headings</td> </tr></table><br/> <center><b><big><big>Arccosine Function Forward Taylor Polynomial Theory</big></big></b></center> If <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>F</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">)</mo> <mo stretchy="false">=</mo> <mi>arccos</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">)</mo> </mrow></math> it follows that <math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><mrow> <msqrt><mrow><mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">*</mo> <mi mathvariant='italic'>x</mi> </mrow> </msqrt> <mo stretchy="false">*</mo> <msup><mi mathvariant='italic'>F</mi> <mrow><mo stretchy="false">(</mo> <mn>1</mn> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">(</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">)</mo> <mo stretchy="false">-</mo> <mn>0</mn> <mo stretchy="false">*</mo> <mi mathvariant='italic'>F</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>u</mi> <mo stretchy="false">)</mo> <mo stretchy="false">=</mo> <mn>-1</mn> </mrow></math> and in the <a href="forwardtheory.xml#Standard Math Functions.Differential Equation" target="_top"><span style='white-space: nowrap'>standard math function differential equation</span></a> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>A</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">)</mo> <mo stretchy="false">=</mo> <mn>0</mn> </mrow></math> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>B</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">)</mo> <mo stretchy="false">=</mo> <msqrt><mrow><mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">*</mo> <mi mathvariant='italic'>x</mi> </mrow> </msqrt> </mrow></math> , and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>D</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">)</mo> <mo stretchy="false">=</mo> <mn>-1</mn> </mrow></math> . We use <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>a</mi> </mrow></math> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>b</mi> </mrow></math> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>d</mi> </mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>z</mi> </mrow></math> to denote the Taylor coefficients for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>A</mi> <mo stretchy="false">[</mo> <mi mathvariant='italic'>X</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">]</mo> </mrow></math> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>B</mi> <mo stretchy="false">[</mo> <mi mathvariant='italic'>X</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">]</mo> </mrow></math> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>D</mi> <mo stretchy="false">[</mo> <mi mathvariant='italic'>X</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">]</mo> </mrow></math> , and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>F</mi> <mo stretchy="false">[</mo> <mi mathvariant='italic'>X</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">]</mo> </mrow></math> respectively. <code><span style='white-space: nowrap'><br/> <br/> </span></code>We define <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>Q</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">)</mo> <mo stretchy="false">=</mo> <mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>x</mi> <mo stretchy="false">*</mo> <mi mathvariant='italic'>x</mi> </mrow></math> and let <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>q</mi> </mrow></math> be the corresponding Taylor coefficients for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>Q</mi> <mo stretchy="false">[</mo> <mi mathvariant='italic'>X</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">]</mo> </mrow></math> . It follows that <math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><mrow> <msup><mi mathvariant='italic'>q</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">=</mo> <mrow><mo stretchy="true">{</mo><mrow><mtable rowalign="center" ><mtr><mtd columnalign="left" > <mn>1</mn> <mo stretchy="false">-</mo> <msup><mi mathvariant='italic'>x</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">*</mo> <msup><mi mathvariant='italic'>x</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="left" > <mrow><mstyle mathvariant='normal'><mi mathvariant='normal'>if</mi> </mstyle></mrow> <mspace width='.3em'/> <mi mathvariant='italic'>j</mi> <mo stretchy="false">=</mo> <mn>0</mn> </mtd></mtr><mtr><mtd columnalign="left" > <mo stretchy="false">-</mo> <munderover><mo displaystyle='true' largeop='true'>∑</mo> <mrow><mi mathvariant='italic'>k</mi> <mo stretchy="false">=</mo> <mn>0</mn> </mrow> <mi mathvariant='italic'>j</mi> </munderover> <msup><mi mathvariant='italic'>x</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> <msup><mi mathvariant='italic'>x</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="left" > <mrow><mstyle mathvariant='normal'><mi mathvariant='normal'>otherwise</mi> </mstyle></mrow> </mtd></mtr></mtable> </mrow><mo stretchy="true"> </mo></mrow> </mrow></math> It follows that <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>B</mi> <mo stretchy="false">[</mo> <mi mathvariant='italic'>X</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">]</mo> <mo stretchy="false">=</mo> <msqrt><mrow><mi mathvariant='italic'>Q</mi> <mo stretchy="false">[</mo> <mi mathvariant='italic'>X</mi> <mo stretchy="false">(</mo> <mi mathvariant='italic'>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">]</mo> </mrow> </msqrt> </mrow></math> and from the equations for the <a href="sqrtforward.xml" target="_top"><span style='white-space: nowrap'>square root</span></a> that for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>j</mi> <mo stretchy="false">=</mo> <mn>0</mn> <mo stretchy="false">,</mo> <mn>1</mn> <mo stretchy="false">,</mo> <mo stretchy="false">…</mo> </mrow></math> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><mrow> <mtable rowalign="center" ><mtr><mtd columnalign="right" > <msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="center" > <mo stretchy="false">=</mo> </mtd><mtd columnalign="left" > <msqrt><mrow><msup><mi mathvariant='italic'>q</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mrow> </msqrt> </mtd></mtr><mtr><mtd columnalign="right" > <msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="center" > <mo stretchy="false">=</mo> </mtd><mtd columnalign="left" > <mfrac><mrow><mn>1</mn> </mrow> <mrow><mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> </mrow> </mfrac> <mfrac><mrow><mn>1</mn> </mrow> <mrow><msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mrow> </mfrac> <mrow><mo stretchy="true">(</mo><mrow><mfrac><mrow><mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> </mrow> <mrow><mn>2</mn> </mrow> </mfrac> <msup><mi mathvariant='italic'>q</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">-</mo> <munderover><mo displaystyle='true' largeop='true'>∑</mo> <mrow><mi mathvariant='italic'>k</mi> <mo stretchy="false">=</mo> <mn>1</mn> </mrow> <mi mathvariant='italic'>j</mi> </munderover> <mi mathvariant='italic'>k</mi> <msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> <msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> </mrow><mo stretchy="true">)</mo></mrow> </mtd></mtr></mtable> </mrow></math> It now follows from the general <a href="forwardtheory.xml#Standard Math Functions.Taylor Coefficients Recursion Formula" target="_top"><span style='white-space: nowrap'>Taylor coefficients recursion formula</span></a> that for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow> <mi mathvariant='italic'>j</mi> <mo stretchy="false">=</mo> <mn>0</mn> <mo stretchy="false">,</mo> <mn>1</mn> <mo stretchy="false">,</mo> <mo stretchy="false">…</mo> </mrow></math> , <math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><mrow> <mtable rowalign="center" ><mtr><mtd columnalign="right" > <msup><mi mathvariant='italic'>z</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="center" > <mo stretchy="false">=</mo> </mtd><mtd columnalign="left" > <mi>arccos</mi> <mo stretchy="false">(</mo> <msup><mi mathvariant='italic'>x</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">)</mo> </mtd></mtr><mtr><mtd columnalign="right" > <msup><mi mathvariant='italic'>e</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="center" > <mo stretchy="false">=</mo> </mtd><mtd columnalign="left" > <msup><mi mathvariant='italic'>d</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">+</mo> <munderover><mo displaystyle='true' largeop='true'>∑</mo> <mrow><mi mathvariant='italic'>k</mi> <mo stretchy="false">=</mo> <mn>0</mn> </mrow> <mrow><mi mathvariant='italic'>j</mi> </mrow> </munderover> <msup><mi mathvariant='italic'>a</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">*</mo> <msup><mi mathvariant='italic'>z</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> </mtd></mtr><mtr><mtd columnalign="right" > </mtd><mtd columnalign="center" > <mo stretchy="false">=</mo> </mtd><mtd columnalign="left" > <mrow><mo stretchy="true">{</mo><mrow><mtable rowalign="center" ><mtr><mtd columnalign="left" > <mn>-1</mn> </mtd><mtd columnalign="left" > <mrow><mstyle mathvariant='normal'><mi mathvariant='normal'>if</mi> </mstyle></mrow> <mspace width='.3em'/> <mi mathvariant='italic'>j</mi> <mo stretchy="false">=</mo> <mn>0</mn> </mtd></mtr><mtr><mtd columnalign="left" > <mn>0</mn> </mtd><mtd columnalign="left" > <mrow><mstyle mathvariant='normal'><mi mathvariant='normal'>otherwise</mi> </mstyle></mrow> </mtd></mtr></mtable> </mrow><mo stretchy="true"> </mo></mrow> </mtd></mtr><mtr><mtd columnalign="right" > <msup><mi mathvariant='italic'>z</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="center" > <mo stretchy="false">=</mo> </mtd><mtd columnalign="left" > <mfrac><mrow><mn>1</mn> </mrow> <mrow><mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> </mrow> </mfrac> <mfrac><mrow><mn>1</mn> </mrow> <mrow><msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mrow> </mfrac> <mrow><mo stretchy="true">(</mo><mrow><munderover><mo displaystyle='true' largeop='true'>∑</mo> <mrow><mi mathvariant='italic'>k</mi> <mo stretchy="false">=</mo> <mn>0</mn> </mrow> <mi mathvariant='italic'>j</mi> </munderover> <msup><mi mathvariant='italic'>e</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> <msup><mi mathvariant='italic'>x</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">-</mo> <munderover><mo displaystyle='true' largeop='true'>∑</mo> <mrow><mi mathvariant='italic'>k</mi> <mo stretchy="false">=</mo> <mn>1</mn> </mrow> <mi mathvariant='italic'>j</mi> </munderover> <msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> <msup><mi mathvariant='italic'>z</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> </mrow><mo stretchy="true">)</mo></mrow> </mtd></mtr><mtr><mtd columnalign="right" > <msup><mi mathvariant='italic'>z</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mtd><mtd columnalign="center" > <mo stretchy="false">=</mo> </mtd><mtd columnalign="left" > <mo stretchy="false">-</mo> <mfrac><mrow><mn>1</mn> </mrow> <mrow><mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> </mrow> </mfrac> <mfrac><mrow><mn>1</mn> </mrow> <mrow><msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </msup> </mrow> </mfrac> <mrow><mo stretchy="true">(</mo><mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">)</mo> <msup><mi mathvariant='italic'>x</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">)</mo> </mrow> </msup> <mo stretchy="false">+</mo> <munderover><mo displaystyle='true' largeop='true'>∑</mo> <mrow><mi mathvariant='italic'>k</mi> <mo stretchy="false">=</mo> <mn>1</mn> </mrow> <mi mathvariant='italic'>j</mi> </munderover> <mi mathvariant='italic'>k</mi> <msup><mi mathvariant='italic'>z</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> <msup><mi mathvariant='italic'>b</mi> <mrow><mo stretchy="false">(</mo> <mi mathvariant='italic'>j</mi> <mo stretchy="false">+</mo> <mn>1</mn> <mo stretchy="false">-</mo> <mi mathvariant='italic'>k</mi> <mo stretchy="false">)</mo> </mrow> </msup> </mrow><mo stretchy="true">)</mo></mrow> </mtd></mtr></mtable> </mrow></math> <hr/>Input File: omh/acos_forward.omh </body> </html>