document.write( "Question 827723: Please prove the following identity
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Algebra.Com's Answer #498857 by Edwin McCravy(20081)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "1-[cos(x)-sin(x)]ē = sin(2x)\r\n" );
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document.write( "To square a binomial write it twice and use FOIL:\r\n" );
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document.write( "1-[cos(x)-sin(x)][cos(x)-sin(x)]\r\n" );
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document.write( "1-[cosē-cos(x)sin(x)-sin(x)cos(x) + sinē(x)]\r\n" );
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document.write( "     The two terms in the middle are the same \r\n" );
document.write( "     so they add together:\r\n" );
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document.write( "1-[cosē(x)-2sin(x)cos(x) + sinē(x)]\r\n" );
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document.write( "     Since cosē(x)+sinē(x)=1\r\n" );
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document.write( "1-[1-2sin(x)cos(x)]\r\n" );
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document.write( "1-1+2sin(x)cos(x)\r\n" );
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document.write( "2sin(x)cos(x)\r\n" );
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document.write( "    Since sin(2x) = 2sin(x)cos(x)\r\n" );
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document.write( "sin(2x)\r\n" );
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document.write( "Edwin
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