I have two questions:
(1)As the tittle, if , is
Just Poisson Equation Where
(2)AND if if , then we have to use superposition of Poisson with zero boundary plus Dirichlet with ?
But I just notice the methodology of solving Heat and Wave equation with non zero boundaries is exactly the same as solving Poisson with non zero boundary. They both use superposition that sum:
1) Dirichlet problem with non zero boundary by assuming and use non zero boundary.
2) Using with zero boundary.