Hi, i need help with simplifying this problem. I think it is an identity, but it looks very complex, and I wanted some other peoples thoughts/opinions. Well here goes.... cos^2((pi/4)-(x-2)) - sin^2((pi/4)-(x-2)) I reduced it using the identity cos2x=cos^2x - sin^2x. I came out with cos2((pi/4)-(x/2)), is that it? Am I looking too far into this, or is there more? Thank you so much in advance!!!!