3.15   A rectangular pipe, running parallel to the z axis (from minus infinity to plus infinity), has three grounded metal sides, at y = 0, y = a, and x = 0. The fourth side, at x = b, is maintained at a specific potential V_o(y).

1. Develop a general formula for the potential inside the pipe.

2. Find the potential explicitly, for the case V_o(y) = V_o ( a constant).