本文给出了Drazin可逆算子在一个扰动下仍然Drazin可逆的充分条件,给出了扰动算子Drazin逆的表达式.同时,并根据其Drazin逆的表达式,得到了其相关的误差估计界.
In this paper,some sufficient conditions for a Drazin invertible operator to be still Drazin invertible under a perturbation are established.The expression for the Drazin inverse of the perturbed operator is derived.Moreover,based on the expression, the bound of the relative error is developed.