0008.tex

\begin{exercise}{M1}{Multiplying matrices}{0008}
\begin{exerciseStatement}

Of the following three matrices, only two may be multiplied. \[
          A= \left[\begin{array}{cccc}
1 & -3 & 3 & 2 \\
2 & -5 & 6 & 1 \\
0 & 0 & 1 & -2
\end{array}\right]  \hspace{1em} B= \left[\begin{array}{ccc}
-1 & -3 & -1 \\
2 & 5 & 2
\end{array}\right]  \hspace{1em} C= \left[\begin{array}{cccc}
1 & 3 & 1 & 5 \\
0 & 0 & 1 & 1
\end{array}\right] \] Explain which two can be multiplied and why. Then show how to find their product.

\end{exerciseStatement}
\begin{exerciseAnswer}\[BA= \left[\begin{array}{cccc}
-7 & 18 & -22 & -3 \\
12 & -31 & 38 & 5
\end{array}\right] \]\end{exerciseAnswer}
\end{exercise}