document.write( "Question 1012353: Verify that the equation is an identity
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Algebra.Com's Answer #628263 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Work with the left side. Factor the numerator as the difference\r\n" );
document.write( "of two squares.\r\n" );
document.write( "Write the denominator as the product of \r\n" );
document.write( "two equal factors:\r\n" );
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document.write( "Cancel:\r\n" );
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document.write( "Use the quotient identities to change everything to sines\r\n" );
document.write( "and cosines:\r\n" );
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document.write( "Multiply top and bottom by LCD = sin(x)cos(x)\r\n" );
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document.write( "\"%28+cos%5E2%28x%29-sin%5E2%28x%29+%29%2F%28cos%5E2%28x%29%2Bsin%5E2%28x%29%29\"\r\n" );
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document.write( "Use the Pythagorean identity to replace the bottom by 1:\r\n" );
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document.write( "\"%28cos%5E2%28x%29-sin%5E2%28x%29%29%2F1\"\r\n" );
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document.write( "\"cos%5E2%28x%29-sin%5E2%28x%29\"\r\n" );
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document.write( "Use the Pythagorean identity to change the sin2(x)\r\n" );
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document.write( "\"cos%5E2%28x%29-%281-cos%5E2%28x%29%5E%22%22%29\"\r\n" );
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document.write( "\"cos%5E2%28x%29-1%2Bcos%5E2%28x%29\"\r\n" );
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document.write( "\"2cos%5E2%28x%29-1\"\r\n" );
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document.write( "Edwin
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