Solve Prob. 4 when u_n = 110 on the upper edge and u = 110 on the other edges.

Data from Prob. 4

Solve the mixed boundary value problem for the Laplace equation ∇²u = 0 in the rectangle in Fig. 458a (using the grid in Fig. 458b) and the boundary conditions u_x = 0 on the left edge, u_x = 3 on the right edge, u = x² on the lower edge, and u = x² - 1 on the upper edge.