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Let:

$$A=\begin{pmatrix}0&1\\\ -1&0\end{pmatrix}$$$$B=\begin{pmatrix}-1&0\\\ 0&1\end{pmatrix}$$

Which of the following matrices are invertible?

Select ALL that apply.

$A$

$B$

$A+B$

$A^T$

$A-B$

$AA^T$