(cos^2(2x))(sin^2(2x))

Question

(cos^2(2x))(sin^2(2x))

Write the expression in terms of first powers of cosine. Simplify as much as possible.

Answer 1

cos²(2x) = 1 + cos(4x)

sin²(2x) = (1-cos(4x))/2

substituting the two values in we get:

cos²(2x)sin²(2x) = (1 + cos(4x)).(1-cos(4x))/2