Calculate the directional derivative of fxy x23 y23 at

Question

1. Calculate the gradient of g(x,y) = x sin y + ycos² x

2. Calculate the directional derivative of f(x,y) = x^2/3 + y^2/3 at the point (1,2) in the direction of v ≤ -3, 5.

3. Calculate the directional derivative of g(x,y) = ln(x + e^y) at the point (e. 1) in the direction of v ≤ e, 1.