$A=\left[\begin{array}{lll}1 & 2 & 3 \\ 4 & 3 & 2\end{array}\right]$, then $\left(A+A^T\right)\left(A-A^T\right)=$
- A
$4\left[\begin{array}{lll}3 & 2 & -3 \\ 3 & 0 & -3 \\ 3 & 2 & -3\end{array}\right]$
- B
$\left[\begin{array}{lll}12 & 8 & 12 \\ 12 & 0 & 12 \\ 12 & 8 & 12\end{array}\right]$
- C
$4\left[\begin{array}{ccc}3 & -2 & -3 \\ 3 & 0 & -3 \\ 3 & -2 & -3\end{array}\right]$
- D
$\left[\begin{array}{lll}-12 & 8 & 12 \\ -12 & 0 & 12 \\ -12 & 8 & 12\end{array}\right]$
✓ Correct answer: A
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