document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=701098>Question 701098</A>: <I><SPAN STYLE=\"word-break: break-all;\"> establish each identity \r<BR>\n" );
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document.write( "A)  sin theta times cos theta over cos^2 theta - sin^2 theta = tan theta over 1 - tan^2 theta </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #432219 by </B><A HREF=/tutors/aboutme.mpl?userid=DrBeeee><B>DrBeeee(684)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=DrBeeee><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=432219\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Rather than typing theta, I'll use x.<BR>\n" );
document.write( "The left side has<BR>\n" );
document.write( "(1) (sin x * cos x)/(cos^2 x - sin^2 x)<BR>\n" );
document.write( "Now divide both numerator and denominator by cos^2 x and get<BR>\n" );
document.write( "(2) (sin x /cos x)/(1-(sin^2 x /cos^2 x))<BR>\n" );
document.write( "Using the identity <BR>\n" );
document.write( "(3) tan x = sin x /cos x<BR>\n" );
document.write( "we get the left side equals<BR>\n" );
document.write( "(4) tan x/(1-tan^2 x)<BR>\n" );
document.write( "which is the same as the given right side, thus demonstrating the identity. </SPAN>\n" );
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