化简f(x)=(1+cos2x)sin^2x

问题描述:

化简f(x)=(1+cos2x)sin^2x

f(x)=(1+cos2x)sin^2x
=(1+cos2x)(1-cos2x)/2
=(1-cos^22x)/2
=sin^22x/2
=[(1-cos4x)/2]/2
=1/4-1/4*cos4x