document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=889493>Question 889493</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Prove the identity: \r<BR>\n" );
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document.write( "Tan^2(x)/(1+tan^2(x)) = sin^2(x) </SPAN>\n" );
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document.write( "you will use the identiTy tan^2(x) + 1 = sec^2(x)\r<BR>\n" );
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document.write( "your equation becomes:\r<BR>\n" );
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document.write( "tan^2(x) / sec^(x) = sin^2(x)\r<BR>\n" );
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document.write( "since sec^(x) = 1/cos^2(x), your equation becomes:\r<BR>\n" );
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document.write( "tan^2(x) * cos^2(x) = sin^2(x)\r<BR>\n" );
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document.write( "since tan^2(x) = sin^2(x) / cos^2(x), your equation becomes:\r<BR>\n" );
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document.write( "sin^2(x) / cos^2(x) * cos^2(x) = sin^2(x)\r<BR>\n" );
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document.write( "the cos^2(x) in the numerator and denominator cancel out and you are left with:\r<BR>\n" );
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document.write( "sin^2(x) = sin^2(x)\r<BR>\n" );
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document.write( "QED (means proof is done)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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