Multiple choice

Let A be the $ 2 × 2 $ matrix with elements $a_{11} = a_{12} = a_{21} = +1 $ and $ a_{22} = −1 $ . Then the eigenvalues of the matrix $A^{19}$ are

$1024$ and $−1024$
$1024\sqrt{2}$ and $−1024 \sqrt{2}$
$4 \sqrt{2}$ and $−4 \sqrt{2}$
$512 \sqrt{2}$ and $−512 \sqrt{2}$

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