Gradient and its applications a) Find V f, where f (x, y) em sin(2xy). b) Find directional derivative of f at P in the direction of a: 3x2 5y , f (x, y) In(x2 + y2), P : (4, O), a = i c) If, on a mountain, the elevation above sea level is f (x, y) = what is the steepest ascent at P : (0.2, 0.1)? 1500