document.write( "Question 279019: sin(x)tan(x/2)=1-cosx\r
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Algebra.Com's Answer #202947 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
\"sin%28x%29tan%28x%2F2%29=1-cos%28x%29\"
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document.write( "There are two half-angle identities for \"tan%28theta%2F2%29\"\r\n" );
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document.write( "They are \r\n" );
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document.write( "\"tan%28theta%2F2%29=sin%28theta%29%2F%281%2Bcos%28theta%29%29\"\r\n" );
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document.write( "and\r\n" );
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document.write( "\"tan%28theta%2F2%29=%281-cos%28theta%29%29%2F%28sin%28theta%29%29\"\r\n" );
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document.write( "We will use the second one:\r\n" );
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document.write( "\"sin%28x%29tan%28x%2F2%29=1-cos%28x%29\"\r\n" );
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document.write( "\"sin%28x%29%28%281-cos%28x%29%29%2Fsin%28x%29%29=1-cos%28x%29\"\r\n" );
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document.write( "\"cross%28sin%28x%29%29%28%281-cos%28x%29%29%2Fcross%28sin%28x%29%29%29=1-cos%28x%29\"\r\n" );
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document.write( "\"1-cos%28x%29=1-cos%28x%29\"\r\n" );
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document.write( "Edwin
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