document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=101196>Question 101196</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a.(1-tan^2u)/(1+tan^2u)=cos(2u)<BR>\n" );
document.write( "   I think this is a half angle identity?verify the identity.\r<BR>\n" );
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document.write( "b. compare the graphs of y1=(1-tan^2u)/(1+tan^2u) and y2=cos(2u) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #73659 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=73659\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> verify the identity.<BR>\n" );
document.write( "a.(1-tan^2u)/(1+tan^2u)=cos(2u)<BR>\n" );
document.write( "(1-tan^2u)/sec^2u = cos^2u-sin^2u<BR>\n" );
document.write( "[1/sec^2u] - [tan^2u/sec^2u] = cos^2u-sin^2u<BR>\n" );
document.write( "cos^2u - sin^2u = cos^2u - sin^2u<BR>\n" );
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document.write( "b. compare the graphs of y1=(1-tan^2u)/(1+tan^2u) and y2=cos(2u)<BR>\n" );
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document.write( "Can't do that on this site.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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