What p₀ in (18) should we choose for Prob. 16? Apply the ADI formulas (17) with that value of p₀ to Prob. 16, performing 1 step. Illustrate the improved convergence by comparing with the corresponding values 0.077, 0.308 after the first step in Prob. 16. (Use the starting values zero.)

Data from Prob. 16

Apply the ADI method to the Dirichlet problem in Prob. 9, using the grid in Fig. 456, as before and starting values zero.

y 3 2 1 P12 P22 P. 11 P 21 1 x 2 3