Mixed-type reverse-order laws of (AB)(1,2,3) and (AB)(1,2,4)

In this paper, by using the extremal ranks of generalized Schur complements, we study the mixed-type reverse-order laws for (AB)(1,2,3) and (AB)(1,2,4), and the sufficient and necessary conditions are established for these two reverse-order laws. Finally, two numerical examples are given to illustrate our results.