y=1/2sin2x-2sinxcosxsinx^2
=1/2sin2x-sin2xsinx^2
=sin2x (1/2-sinx^2)
=1/2 sin2x (1-2sinx^2)
=1/2sin2xcos2x
=1/4sin4x
周期=2派/4=派/2
函数y=sinxcosx-2sinx^3cosx的最小正周期是多少
y=1/2sin2x-2sinxcosxsinx^2
=1/2sin2x-sin2xsinx^2
=sin2x (1/2-sinx^2)
=1/2 sin2x (1-2sinx^2)
=1/2sin2xcos2x
=1/4sin4x
周期=2派/4=派/2