Does any equation holds for inverse(A- B)? [closed]

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is it possible to calculate inverse of A-B, i have calculated inverse of A and B already.

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No, the inverse of A-B is not a nice function of the inverses of A and B. (Of course it's possible to calculate -- if you have the inverses of A and B then you can calculate A and B, hence A-B, hence the inverse of A-B -- but, assuming you knew A and B anyway, knowing their inverses too doesn't help you calculate A-B more efficiently or accurately.)

There are some special cases where you can do something useful. For instance, if one of the matrices has rank 1 then this is basically the Sherman-Morrison formula. But in general you're out of luck.