Change (-3,3,3) to cylindrical coordinates. I'm doing r^2 = x^2 + y^2, which I find r = sqrt(18) = 3radical(2) tan(theta) = 3/-3 = 1, so theta = -pi/4 = 7pi/4. z = 3 Cylindrical coordinates are (3sqrt(2),7pi/4,3). Is this right? Correct answer to the homework says 3pi/4 for the angle, for some reason.