2. We want to find the absolute maximum value of f (x, y) = 23 - 3x - y2 + 12 on the domain D = {(x, y) |x2 +y2 0}, a half disk. (a) First, find the critical points of f, and determine if any of the critical points is a local maximum in the domain D. (b) Then, find the (absolute) maximum value of f along the boundary of D: the bottom edge of D and along the top arc of D. (Note: some of the values might be a bit messy. Give solutions to two decimal places.) (c) Using parts (a) and (b), find the absolute maximum value of f on D