1.4.6 Matrix transformations

Condition: Perform operations on matrices: \( A \cdot B+3 \cdot C \cdot B, \quad \) where \( A=\left(\begin{array}{ccc}2 & 1 & -1 \\ 3 & 2 & 2\end{array}\right) \), \( B=\left(\begin{array}{cc}1 & 5 \\ 2 & 1 \\ 1 & -1\end{array}\right), C=\left(\begin{array}{lll}3 & 4 & 2 \\ 2 & 1 & 1\end{array}\right) \)