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arXiv · 1307.7229

Additive and product properties of Drazin inverses of elements in a ring

Huihui Zhu·Jianlong Chen
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Abstract

We study the Drazin inverses of the sum and product of two elements in a ring. For Drazin invertible elements $a$ and $b$ such that $a^2b=aba$ and $b^2a=bab$, it is shown that $ab$ is Drazin invertible and that $a+b$ is Drazin invertible if and only if $1+a^Db$ is Drazin invertible. Moreover, the formulae of $(ab)^D$ and $(a+b)^D$ are presented. Thus, a generalization of the main result of Zhuang, Chen et al. (Linear Multilinear Algebra 60 (2012) 903-910) is given.

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Huihui Zhu, Jianlong Chen. 2013-07-27. Additive and product properties of Drazin inverses of elements in a ring. https://arxiv.org/abs/1307.7229

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