On nonsingularity and group invertibility of combinations of two group invertible matrices

Ela on the Group Inverse of Linear Combinations of Two Group Invertible Matrices

hold. If such matrix X exists, then it is unique, denoted by A, and called the group inverse of A. It is well known that the group inverse of a square matrix A exists if and only if rank(A) = rank(A) (see, for example, [1, Section 4.4] for details). Clearly, not every matrix is group invertible. It is straightforward to prove that A is group invertible if and only if A is group invertible, and ...

On the group inverse of linear combinations of two group invertible matrices

faculty of psychology and social sciences group of anthropology master thesis in major of anthropology

چکیده پایان نامه (شامل خلاصه، اهداف، روش های اجرا و نتایج به دست آمده): کار جمع آوری گو یش های محلی در سال های اخیر شتاب امیدوار کننده ای به خود گرفته است. شاید از بارزترین اهداف جمع آوری گویش های مختلف، ثبت و ضبط آن، جلوگیری از نابودی و مهمتر از همه حل مشکلات دستوری زبان رسمی باشد. دقت در فرآیند های زبانی گویش های محلی نوع ارتباط مردم نواحی مختلف با پیرامون نشان را به ما نشان خواهد داد. از س...

On Nonsingularity of Linear Combinations of Tripotent Matrices

Let T1 and T2 be two commuting n × n tripotent matrices and c1, c2 two nonzero complex numbers. The problem of when a linear combination of the form T = c1T1 + c2T2 is nonsingular is considered. Some other nonsingularitytype relationships for tripotent matrices are also established. Moreover, a statistical interpretation of the results is pointed out.

On Nonsingularity of Block Two-by-Two Matrices

We derive necessary and sufficient conditions for guaranteeing the nonsingularity of a block two-by-two matrix by making use of the singular value decompositions and the Moore-Penrose pseudoinverses of the matrix blocks. These conditions are complete, and much weaker and simpler than those given by Decker and Keller (J. Math. Anal. Appl. 75(1980)417-430), and may be more easily examined than th...