Question 7 3 pts . Use first order backward difference approximation with step h = 0.1 to determine the first derivative of f ( ) = a sina at x = 2. f (2) = (round to the one decimal place, use radians) . Laplace operator A is discretized using central differences on a square grid with step h, - hy = 1. Determine A f at point (1, 2) for f(x, y) = x2y