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Results tagged with nilpotent-matrices
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user 6827
29
votes
Accepted
When is $\ker AB = \ker A + \ker B$?
Since $\ker A = \ker A^2$, the map $\bar{A} : V/\ker A \to V/\ker A$ is injective. Since $V/\ker A$ is finite dimensional, this map is surjective. So for any $x \in V$ we can find $y \in V$ and $z \in …
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