2. Let f(:1:,y) = 1 2sin2a: y2/4. (a) Calculate V f (7r/4, 0). (b) Find the directional derivative of f in the direction at the point (Tr/4, 0). (c) The level curves of f are given below. If f represented a hill, the point (0,0) would be a summit. Starting at (1, 1), sketch the path which gives the quickest ascent. Justify your sketch