Use difference quotients with Ax = 0.1 and Ay = 0.1 to estimate fx (1,3) and fy (1,3) where f(x, y) = ex sin(y). fx(1,3)= fy(1,3)= Then give better estimates by using Ax = 0.01 and Ay = 0.01. fx(1,3) fy(1,3)=