Answer
$\begin{bmatrix}5&-2\\1&-1\\4&-1\end{bmatrix}$
Work Step by Step
We are given the matrices:
$A=\begin{bmatrix}3&1\\1&0\\2&1\end{bmatrix}$
$B=\begin{bmatrix}1&-1\\2&1\end{bmatrix}$
Compute $AB$:
$AB=\begin{bmatrix}3&1\\1&0\\2&1\end{bmatrix}\begin{bmatrix}1&-1\\2&1\end{bmatrix}$
$=\begin{bmatrix}3+2&-3+1\\1+0&-1+0\\2+2&-2+1\end{bmatrix}$
$=\begin{bmatrix}5&-2\\1&-1\\4&-1\end{bmatrix}$
