Найти матрицу D=AB-2C задача во вложении

Решите задачу:

$A*B= \left[\begin{array}{cc}-3&0\\0&1\\1&0\end{array}\right] * \left[\begin{array}{cc}4&3\\1&-2\end{array}\right] =\left[\begin{array}{cc}-12&-9\\1&-2\\4&3\end{array}\right]$

$AB-2C=\left[\begin{array}{cc}-12&-9\\1&-2\\4&3\end{array}\right] -2*\left[\begin{array}{cc}-2&1\\0&3\\0&-1\end{array}\right] =$
$=\left[\begin{array}{cc}-12&-9\\1&-2\\4&3\end{array}\right] -\left[\begin{array}{cc}-4&2\\0&6\\0&-2\end{array}\right] =\left[\begin{array}{cc}-8&-11\\1&-8\\4&5\end{array}\right]$