document.write( "Question 551204: Prove that
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Algebra.Com's Answer #359528 by Edwin McCravy(20060) $\"\"$ $\"About$

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Prove that
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document.write( "I will simplify the right side until it becomes the left side:\r\n" );
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document.write( "2sin(45°+A)cos(45°+B)\r\n" );
document.write( "2[sin(45°)cos(A) + cos(45)sin(A)][cos(45°)cos(B) - sin(45°)sin(B)]\r\n" );
document.write( "2[cos(A) + sin(A)][cos(B)-sin(B)]\r\n" );
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document.write( "2[cos(A) + sin(A)][cos(B)-sin(B)]\r\n" );
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document.write( "2[cos(A) + sin(A)][cos(B)-sin(B)]\r\n" );
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document.write( "[cos(A) + sin(A)][cos(B)-sin(B)]\r\n" );
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document.write( "(1)[cos(A) + sin(A)][cos(B)-sin(B)]\r\n" );
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document.write( "[cos(A) + sin(A)][cos(B)-sin(B)]\r\n" );
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document.write( "cos(A)cos(B) - cos(A)sin(B) + sin(A)cos(B) - sin(A)sin(B)\r\n" );
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document.write( "Rearrange terms:\r\n" );
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document.write( "cos(A)cos(B) - sin(A)sin(B) + sin(A)cos(B) - cos(A)sin(B)\r\n" );
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document.write( "[cos(A)cos(B) - sin(A)sin(B)] + [sin(A)cos(B) - cos(A)sin(B)]\r\n" );
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document.write( "cos(A+B) + sin(A-B)\r\n" );
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document.write( "Edwin

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