You can put this solution on YOUR website! -cos(x+y)sin(y)+sin(x+y)cos(y)
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Formula: sin(A-B) = sin(A)cos(B)-cos(A)sin(B)
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Your problem rearranged:
sin(x+y)cos(y) - cos(x+y)sin(y)
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Comparing the two forms:
A = x+y
B = y
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A-B = x
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Your Answer:
-cos(x+y)sin(y)+sin(x+y)cos(y) = sin[(x+y)-y)] = sin(x)
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Cheers,
Stan H.
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