On The Drazin Inverse And M-P Inverse For Sum Of Matrices

Drazin inverse and M-P inverse have many important applications in the aspects of theoretic research of operator and statistics. In this article, we will exhibit under suitable conditions a neat relationship between the Drazin inverse of A + B and the Drazin inverses of the individual terms A and B. Furthermore, with the same thread, we will give an expression of the M-P inverse of A + B in terms of only the M-P inverses of matrices A and B.