# Math Help - similar matrices

1. ## similar matrices

Let $A, B$ be square matrices of order $n$.
If $A$ or $B$ is invertible, show that $AB$ is similar to $AB$.

First I saw this question, I think there' s a typo in this question since every matrix is similar to itself.
May be it should be $AB$ similar to $BA$.

Anyway, i still can't solve it if it is $BA$.

2. Think about what you know.
You know that A has an inverse (or similarly for B).
So $A^{-1}$ exists. So chances are it's going to be very closely related to your similarity transformation.
Hope that helps.