1. The problem statement, all variables and given/known data Does [sin(θ/2)-cos(θ/2)]^2 equal 1 for all values of θ? I need to figure this out to solve a physics problem. 2. Relevant equations sin^2(A)+cos^2(A)=1 3. The attempt at a solution [sin(θ/2)-cos(θ/2)]^2 =sin^2(θ/2)+cos^2(θ/2) =1 But this isn't what I get when I put f(x)=[sin(θ/2)-cos(θ/2)]^2 in my graphing calculator. What's going on???