## [HW4 Q1.2] Not sure if my approach is correct

I am not sure if this is what you mean that we use Gauss' Law. Also, I am not sure how to integrate this to obtain a BC at r=R (how do I integrate something with f(g(x)dx when I do not know how g(x) depends on x?). Form this I can only gather that at R, we must have a surface charge density but not sure how to express it. Is this the right approach?