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arXiv · 1003.1602

The expression of Moore--Penrose inverse of $A-XY^*$

Fapeng Du·Yifeng Xue
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Abstract

Let $K,\,H$ be Hilbert spaces and let $L(K,H)$ denote the set of all bounded linear operators from $K$ to $H$. Let $A \in L(H)\triangleq L(H,H)$ with $R(A)$ closed and $X,Y \in L(K,H)$ with $R(X)\subseteq R(A),R(Y)\subseteq R(A^*)$. In this short note, we give some new expressions of the Moore--Penrose inverse $(A-XY^*)^+$ of $A-XY^*$ under certain suitable conditions.

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Fapeng Du, Yifeng Xue. 2010-03-08. The expression of Moore--Penrose inverse of $A-XY^*$. https://arxiv.org/abs/1003.1602

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