0008.ptx

<exercise checkit-seed="0008" checkit-slug="M4" checkit-title="Finding a matrix inverse">
  <statement>
    <p>Show how to find the inverse of the matrix <m>Q= \left[\begin{array}{cccc}
-2 &amp; 5 &amp; 1 &amp; 8 \\
-1 &amp; 2 &amp; 6 &amp; 5 \\
-2 &amp; 1 &amp; 1 &amp; 7 \\
1 &amp; -2 &amp; -1 &amp; -4
\end{array}\right] </m>.</p>
  </statement>
  <answer>
    <me>Q^{-1}= \left[\begin{array}{cccc}
-49 &amp; -13 &amp; -17 &amp; -144 \\
4 &amp; 1 &amp; 1 &amp; 11 \\
3 &amp; 1 &amp; 1 &amp; 9 \\
-15 &amp; -4 &amp; -5 &amp; -44
\end{array}\right] </me>
  </answer>
</exercise>