Question

sin2x +sin3x/cos2x-cos3x=cotx/2






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Answer 1

Answer:

cos(a)sin(b)=12(sin(a+b)−sin(a−b))

sin(a)cos(b)=12(sin(a+b)+sin(a−b))

You can quite easily sub in a and b

sin(3x)cos(2x)+cos(3x)sin(2x)=12(sin(3x+2x)+sin(3x−2x))+12(sin(3x+2x)−sin(3x−2x))=12(sin(3x+2x))+12(sin(3x+2x))=sin(5x)