Repeat Exercise 56 for the function

Data from Exercises 56

Let F(x, y) = x² + 2xy − y².

a. If F(x, y) = k for constant k, use the method of implicit differentiation developed in Chapter 2 to find.

b. Find the partial derivatives F_x and F_y and verify that

F(x, y) = xex + y X + x ln(x + y)