第五题函数周期怎么算

网友回答

4sin^3(x)cosx = 2sin^2(x) * 2sinxcosx = (1-cos2x) * sin2x = sin2x - sin2xcos2x = sin2x - (1/2)sin4x
所以f(x) = (1/2)sin4x
其最小正周期是pi/2,选C