a Jack son 2. A function f(x,y)-V12-x2-yī and the point P(-1,v1) are given. Let θ correspond to the direction of the directional derivative. a. Find the gradient Vf(x,y) and evaluate it at P. b. Find the angles θ (with respect to the positive x-axis) associated with the direction of maximum increase, maximum decrease and zero change. Write the directional derivative at P as a function of 8; call it g(o). c. d. Use calculus I, to find the value of θ that maximizes g (0) and find the maximum value.