document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1023431>Question 1023431</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How to find the identify?<BR>\n" );
document.write( "Sec^2(x) - sin^2(x) = cos^2(x) + tan^2(x)<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #638934 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=638934\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You meant:  How to prove the identity, right?\r<BR>\n" );
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document.write( "We prove it this way.\r<BR>\n" );
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document.write( "Start with the identity <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sec%5E2%28x%29+=+1%2Btan%5E2%28x%29 ALIGN=MIDDLE  ALT=\"sec%5E2%28x%29+=+1%2Btan%5E2%28x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sec%5E2%28x%29+-+sin%5E2%28x%29+=+-sin%5E2%28x%29++%2B+sin%5E2%28x%29+%2B+cos%5E2%28x%29+%2Btan%5E2%28x%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "==>  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sec%5E2%28x%29+-+sin%5E2%28x%29+=+cos%5E2%28x%29+%2Btan%5E2%28x%29 ALIGN=MIDDLE  ALT=\"sec%5E2%28x%29+-+sin%5E2%28x%29+=+cos%5E2%28x%29+%2Btan%5E2%28x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and the original identity is proved... </SPAN>\n" );
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