|
|
★ 小木虫: 金币+0.5, 给个红包,谢谢回帖
The matrices $AB$ and $BA$ are similar provided either $A$ or $B$ is invertible.
If both $A$ and $B$ are singular (and square), a limiting argument involving $A +\epsilon I$
is useful. In this case $AB$ and $BA$ still have the same eigenvalues with the same
multiplicities. However, in general, $AB$ is not similar to $BA$, . Their Jordan forms may be different, in the sizes of the blocks associated with the eigenvalue $0$. |
|