I want to solve the boundary value problem:
Laplace's equation for u(r, theta) = 0, 1 < r < 2, 0 < theta < a
(i) ur(1,theta) = 0
(ii) ur(2,theta) = 0
(iii) u(r,0) = 0
(iv) u(r,a) = f(r)
I let u(r,theta) = R(r)M(theta) and plug this into the DE.
It's too tough...