A direct computational method for determining the maximal (A, B)-invariant subspace contained in kerC

A useful method for calculation of the maximal (
A, B
)- invariant subspace contained in
\ker C
is presented. The method demands reduction of certain matrices into echelon form and application of rank test for low-dimensional real matrices. The approach presented allows unification of the approach of Bhattacharyya, Vardulakis, and Wonham.