document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=199298>Question 199298</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/1559536063/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> prove each identity, SHOW WORK\r<BR>\n" );
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document.write( "a. cos(2(3.14)-A)=cos A\r<BR>\n" );
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document.write( "b. sin((3(3.14)/2)-A)=-cosA\r<BR>\n" );
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document.write( "c. use the identity for sin(A+B) to prove the identity sin2A=2sinAcosA\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #149750 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=149750\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I'll do the first one to get you started. Note: I'll use <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi ALIGN=MIDDLE  ALT=\"pi\"   DISABLED_style= \"max-width:90%; height:auto;\" > for 3.14\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%282pi-A%29=cos%28A%29 ALIGN=MIDDLE  ALT=\"cos%282pi-A%29=cos%28A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the given equation.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%282pi%29cos%28A%29%2Bsin%282pi%29sin%28A%29=cos%28A%29 ALIGN=MIDDLE  ALT=\"cos%282pi%29cos%28A%29%2Bsin%282pi%29sin%28A%29=cos%28A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Expand\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%29cos%28A%29%2B%280%29sin%28A%29=cos%28A%29 ALIGN=MIDDLE  ALT=\"%281%29cos%28A%29%2B%280%29sin%28A%29=cos%28A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Evaluate the cosine of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2pi ALIGN=MIDDLE  ALT=\"2pi\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get 1. Evaluate the sine of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2pi ALIGN=MIDDLE  ALT=\"2pi\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get 0\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28A%29%2B0=cos%28A%29 ALIGN=MIDDLE  ALT=\"cos%28A%29%2B0=cos%28A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28A%29=cos%28A%29 ALIGN=MIDDLE  ALT=\"cos%28A%29=cos%28A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify\r<BR>\n" );
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document.write( "So this verifies the identity. </SPAN>\n" );
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