0007.tex

\begin{exercise}{M1}{Multiplying matrices}{0007}
\begin{exerciseStatement}

Of the following three matrices, only two may be multiplied. \[
          A= \left[\begin{array}{cccc}
1 & 0 & -3 & 1 \\
1 & 1 & -5 & 1
\end{array}\right]  \hspace{1em} B= \left[\begin{array}{ccc}
-1 & 2 & 4 \\
1 & -3 & -5
\end{array}\right]  \hspace{1em} C= \left[\begin{array}{cccc}
1 & 5 & 3 & 2 \\
-1 & 0 & -4 & 5 \\
0 & -4 & 1 & -6
\end{array}\right] \] Explain which two can be multiplied and why. Then show how to find their product.

\end{exerciseStatement}
\begin{exerciseAnswer}\[BC= \left[\begin{array}{cccc}
-3 & -21 & -7 & -16 \\
4 & 25 & 10 & 17
\end{array}\right] \]\end{exerciseAnswer}
\end{exercise}