document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=919184>Question 919184</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do I prove that \r<BR>\n" );
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document.write( "1-2cos^2x = sinxcosx(tanx-cotx)\r<BR>\n" );
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document.write( "I'm really confused at trigonometric identities that involve reciprocal in general.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #557535 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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/cgi-bin/show-face.mpl?user=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=557535\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How do I prove that \r<BR>\n" );
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document.write( "1-2cos^2x = sinxcosx(tanx-cotx)<BR>\n" );
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document.write( "Convert tan and cot to sine & cosine<BR>\n" );
document.write( "1-2cos^2x = sinxcosx(sin/cos - cos/sin)<BR>\n" );
document.write( "1 - 2cos^2x = sin^2 - cos^2<BR>\n" );
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document.write( "Can you do the rest?<BR>\n" );
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