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matrix-multiply-calculator
\begin{pmatrix} 1 & 0 & 0 \\ 1 & 0 & 1 \\ 0 & 1 & 1\end{pmatrix}\begin{pmatrix}2 & 0 & 1 \\ 1 & 1 & 1 \\ -1 & 0 & 0\end{pmatrix}-\begin{pmatrix} 1 & 1 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{pmatrix}\begin{pmatrix} 1 & 0 & 0 \\ 1 & 0 & 1 \\ 0 & 1 & 1\end{pmatrix}
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