Question Detail
Question
∫sin(2x)·cos(x) dx
Correct Answer
Option A is the correct answer.
Detailed Explanation
sin2x = 2sinx cosx, so sin2x·cosx = 2sinx cos²x. Substituting u=cosx: ∫-2u²du = -2/3 u³+C = -2/3 cos³x+C.
Hint
Rewrite sin2x as 2sinx cosx first, then substitute u=cosx.