It is known that, in general, the coboundary polynomial and the M\"obius
polynomial of a matroid do not determine each other. Less is known about more
specific cases. In this paper, we will try to answer if it is possible that the
M\"obius polynomial of a matroid, together with the M\"obius polynomial of the
dual matroid, define the coboundary polynomial of the matroid. In some cases,
the answer is affirmative, and we will give two constructions to determine the
coboundary polynomial in these cases.Comment: 12 page