<exercise checkit-seed="0011" checkit-slug="A2" checkit-title="Standard matrices">
<statement>
<ol>
<li>Find the standard matrix for the linear transformation <m>S:\mathbb{R}^ 3 \to \mathbb{R}^ 2 </m> given by
<me>S\left( \left[\begin{array}{c}
x \\
y \\
z
\end{array}\right] \right) = \left[\begin{array}{c}
-x + 4 \, y + 2 \, z \\
2 \, x - 8 \, y - 5 \, z
\end{array}\right] .</me></li>
<li>Let <m>T:\mathbb{R}^ 3 \to \mathbb{R}^ 4 </m> be the linear transformation given by the standard matrix
<me> \left[\begin{array}{ccc}
0 & -2 & -5 \\
-1 & 6 & 4 \\
0 & -5 & -4 \\
-1 & 3 & -2
\end{array}\right] .</me>
Compute <m>T\left( \left[\begin{array}{c}
-6 \\
5 \\
4
\end{array}\right] \right)</m>.
</li>
</ol>
</statement>
<answer>
<ol>
<li>
<me> \left[\begin{array}{ccc}
-1 & 4 & 2 \\
2 & -8 & -5
\end{array}\right] </me>
</li>
<li>
<me>T\left( \left[\begin{array}{c}
-6 \\
5 \\
4
\end{array}\right] \right)= \left[\begin{array}{c}
-30 \\
52 \\
-41 \\
13
\end{array}\right] </me>
</li>
</ol>
</answer>
</exercise>