∫ sin x cos 2x sin 3x dx

We know 2sinAcosB = sin(A + B) + sin(A – B)


sin3xcos2x =


The given equation becomes




We know 2sinAsinB = cos(A – B) – cos(A + B)


sin5xsinx =


Also sin2x =


Above equation can be written as




We know





NOTE: – Whenever you are solving integral questions having trigonometric functions in the product then the first thing that should be done is convert them in the form of addition or subtraction.


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