If sin(2x) = 2sin x cos x, find all possible values of x in [0, 2π).
Correct: A
We are given sin(2x) = 2sin x cos x, but 2sin x cos x = sin(2x). So sin(2x) = sin(2x). This is always true for any value of x in [0, 2π), because both sides are equal to the same function of x. Thus x can be any angle in [0, 2π).