\begin{exercise}{G1}{Row operations and determinants}{0002}
\begin{exerciseStatement}
Let \(A\) be a \(4 \times 4\) matrix with determinant \( 7 \).
\begin{enumerate}[(a)]
\item Let \(B\) be the matrix obtained from \(A\) by applying the row operation \( R_3 \leftrightarrow R_1 \). What is \(\operatorname{det}\ B\)?
\item Let \(P\) be the matrix obtained from \(A\) by applying the row operation \( R_2 \to R_2 + 5R_3 \). What is \(\operatorname{det}\ P\)?
\item Let \(M\) be the matrix obtained from \(A\) by applying the row operation \( R_1 \to 3R_1 \). What is \(\operatorname{det}\ M\)?
\end{enumerate}
\end{exerciseStatement}
\begin{exerciseAnswer}
\begin{enumerate}[(a)]
\item \(\operatorname{det}\ B= -7 \)
\item \(\operatorname{det}\ P= 7 \)
\item \(\operatorname{det}\ M= 21 \)
\end{enumerate}
\end{exerciseAnswer}
\end{exercise}