1. The problem statement, all variables and given/known data What's the hypotenuse of acosx + bsinx = c and by extension sinx - sqrt(2)cosx = 1 ? 2. Relevant equations 3. The attempt at a solution If cosx = x and sinx = y and a^2 + b^2 = c^2, then going by acosx + bsinx = c the hypotenuse of sinx - sqrt(2)cosx = 1 have to be sqrt(c)= 1? Then how about 1^2 + (- sqrt(2))^2= 3, where c= sqrt(3)? Thanks.