0002.ptx

<exercise checkit-seed="0002" checkit-slug="G1" checkit-title="Row operations and determinants">
  <statement>
    <p>Let <m>A</m> be a <m>4 \times 4</m> matrix with determinant <m> 7 </m>.</p>
    <ol>
      <li>Let <m>B</m> be the matrix obtained from <m>A</m> by applying the row operation <m> R_3 \leftrightarrow R_1 </m>.
              What is <m>\operatorname{det}\ B</m>?</li>
      <li>Let <m>P</m> be the matrix obtained from <m>A</m> by applying the row operation <m> R_2 \to R_2 + 5R_3 </m>.
              What is <m>\operatorname{det}\ P</m>?</li>
      <li>Let <m>M</m> be the matrix obtained from <m>A</m> by applying the row operation <m> R_1 \to 3R_1 </m>.
              What is <m>\operatorname{det}\ M</m>?</li>
    </ol>
  </statement>
  <answer>
    <ol>
      <li>
        <m>\operatorname{det}\ B= -7 </m>
      </li>
      <li>
        <m>\operatorname{det}\ P= 7 </m>
      </li>
      <li>
        <m>\operatorname{det}\ M= 21 </m>
      </li>
    </ol>
  </answer>
</exercise>