1. The problem statement, all variables and given/known data The space between two long coaxial conducting cylinders is filled with an inhomogeneous dielectric. Show that the E field can be made independent of position between the cylinders by an appropriate choice for the radial variation of the dielectric constant. 2. Relevant equations I thought about starting with the "Gauss's Law" for dielectrics where [tex]D=\epsilon E[/tex] is substituted for the electric field. 3. The attempt at a solution My first approach was to try and calculate the electric field between the two cylinders by choosing an arbitrary Gaussian surface inside the dielectric material. But I'm not sure how to carry out that integral for this problem if I have to show the E field is invariant and I can't assume it. Any tips or hints would be great, thanks!