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Algebra.Com's Answer #173432 by Edwin McCravy(20060) $\"\"$ $\"About$

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$\"%28sin%28x%29%2Bsin%283x%29%29%2F%28cos%28x%29%2Bcos%283x%29%29=tan%282x%29\"$
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document.write( "Work with only the left side:\r\n" );
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document.write( "Write  as  and  as \r\n" );
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document.write( "Use the identities\r\n" );
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document.write( "and \r\n" );
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document.write( "to rewrite the numerator and\r\n" );
document.write( "use the identities \r\n" );
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document.write( "and\r\n" );
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document.write( "to rewrite the denominator \r\n" );
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document.write( "Remove the parentheses\r\n" );
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document.write( "Cancel:\r\n" );
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document.write( "The two terms on top are like terms, and\r\n" );
document.write( "the two terms on the bottom are also like terms\r\n" );
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document.write( "Cancel the 2'a and the cosines:\r\n" );
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document.write( "Use identity \r\n" );
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document.write( "Edwin

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