SOLUTION: Verify the identity. sin (x + y) - sin (x - y) = 2 cos x sin y

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Question 641428: Verify the identity.
sin (x + y) - sin (x - y) = 2 cos x sin y

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
sin(x + y) - sin(x - y) = 2cos(x)sin(y)

sin(x)cos(y) + cos(x)sin(y) - (sin(x)cos(y) - cos(x)sin(y)) = 2cos(x)sin(y)

sin(x)cos(y) + cos(x)sin(y) - sin(x)cos(y) + cos(x)sin(y) = 2cos(x)sin(y)

2cos(x)sin(y) = 2cos(x)sin(y)

So that verifies the identity