document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=929094>Question 929094</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need to prove the identity.\r<BR>\n" );
document.write( "\n" );
document.write( "(cos 2x) / (1 - tan^2 x) = cos^2 x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #564088 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=564088\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> prove the identity. <BR>\n" );
document.write( "(cos 2x) / (1 - tan^2 x) = cos^2 x<BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "Multiply both sides by (1-tan^2(x)) to get:<BR>\n" );
document.write( "cos(2x) = cos^2(x) - sin^2(x)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "cos(2x) = cos(2x)<BR>\n" );
document.write( "------------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "------------------ </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );