Question

4 sin^2x cos^2x+4 cos^4x-4 cos^2x+ 1

Answer 1

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