document.write( "Question 1048795: Express sin(x)sin(x-y) as a difference of two cosines. \n" ); document.write( "

Algebra.Com's Answer #664551 by Edwin McCravy(20067) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Subtract the 2nd equation from the 1st:\r\n" );
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document.write( "Multiply both sides by 1/2\r\n" );
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document.write( "Let A = x and B = x-y\r\n" );
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document.write( "That's ONE-HALF the difference of two cosines, which may be what\r\n" );
document.write( "you want.  If not let me know in the thank-you note form below,\r\n" );
document.write( "and I'll try to get rid of the ONE-HALF.\r\n" );
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document.write( "Edwin

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