Use the power-reducing identities to write #sin^2xcos^2x# in terms of the first power of cosine?

1 Answer
Mar 13, 2018

#sin^2xcos^2x=(1-cos(4x))/8#

Explanation:

#sin^2x=(1-cos(2x))/2#

#cos^2x=(1+cos(2x))/2#

#sin^2xcos^2x=((1+cos(2x))(1-cos(2x)))/4=(1-cos^2(2x))/4#

#cos^2(2x)=(1+cos(4x))/2#

#(1-(1+cos(4x))/2)/4=(2-(1+cos(4x)))/8=(1-cos(4x))/8#