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 #557534 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=557534\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> sinxcosx(tanx-cotx)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28x%29cos%28x%29%28%28tan%5E2%28x%29+-+1%29%2Ftan%28x%29+%29%29 ALIGN=MIDDLE  ALT=\"sin%28x%29cos%28x%29%28%28tan%5E2%28x%29+-+1%29%2Ftan%28x%29+%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "( cosx/sinx)(sinxcosx)(tan^2x - 1)<BR>\n" );
document.write( "cos^2 (tan^2x - 1)<BR>\n" );
document.write( "sin^2 - cos^2<BR>\n" );
document.write( "(1 - cosx^2) - cosx^2<BR>\n" );
document.write( "1 - 2cosx^2 </SPAN>\n" );
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