Please, help me.
I have to find the Green's function in the following region, but I don't have any idea how to find it:
I have a conducting spherical shell of radius a; in the center there are 2 spherical shells of radius b both and charge -q, they are a distance d from their centers, and they both have a charge +q in the center. I'm supposed to find Green's function for Dirichlet conditions on the region surrounding the inner spheres.
Here's a image for the problem.
I tried using method of images but I'm not quite sure where should I put image charges. I also tried using spherical coordinates, by describing the inner spheres by a non origin centred sphere equation for boundary conditions, but in this case but I'm not sure how to divide regions for primed and not primed coordinates.