2. Let f(x, y)= x 2 sin(y).(a) Find the gradient of f(x, y).(b) Find the directional derivative of f(x, y) in the direction of v =1,1 at the point P =2,13.(c) Let r(t)=t 2,3t. Use the Chain Rule to calculate d dtf(r(t)) at t =1.(d) Let F(t)= t 2+1. Use the Chain Rule to calculate F(f(x, y)).(e) Determine the direction in which f has maximum rate of increase from the point 2,13 and give the rate of change in that direction