cos^8(x) - sin^8(x) + (1/4)sin2xsin4x = [cos^4(x) + sin^4(x)]*[cos^4(x) - sin^4(x)] + (1/4)*sin2x * 2*sin2x*cos2x=[cos^4(x) + 2*cos^2(x)*sin^2(x) + sin^4(x) - 2*cos^2(x)*sin^2(x)] * [cos^2(x) + sin^2(...