Jordan canonical form from rational canonical form: Let VV be a finite-dimensional vector space over a field FF, and let T:VVT:V\to V be linear. Assume the characteristic polynomial of TT splits over FF (for example, FF is algebraically closed). Then there exists a basis of VV for which the matrix of TT is in Jordan canonical form.

This follows by refining the invariant-factor decomposition in into primary factors, yielding the ; the Jordan blocks are organized by the roots of the .