<item ident="M4-0004" title="M4 | Finding a matrix inverse | ver. 0004"> <itemmetadata> <qtimetadata> <qtimetadatafield> <fieldlabel>question_type</fieldlabel> <fieldentry>essay_question</fieldentry> </qtimetadatafield> </qtimetadata> </itemmetadata> <presentation> <material> <mattextxml> <div class="exercise-statement"> <p> <strong>M4.</strong> </p> <p>Show how to find the inverse of the matrix <img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?M= \left[\begin{array}{cccc} -3 & 1 & -1 & -1 \\ -1 & 0 & 0 & 1 \\ 1 & 1 & 4 & 8 \\ -2 & 0 & -2 & -3 \end{array}\right]" alt="M= \left[\begin{array}{cccc} -3 & 1 & -1 & -1 \\ -1 & 0 & 0 & 1 \\ 1 & 1 & 4 & 8 \\ -2 & 0 & -2 & -3 \end{array}\right]" title="M= \left[\begin{array}{cccc} -3 & 1 & -1 & -1 \\ -1 & 0 & 0 & 1 \\ 1 & 1 & 4 & 8 \\ -2 & 0 & -2 & -3 \end{array}\right]" data-latex="M= \left[\begin{array}{cccc} -3 & 1 & -1 & -1 \\ -1 & 0 & 0 & 1 \\ 1 & 1 & 4 & 8 \\ -2 & 0 & -2 & -3 \end{array}\right]"/>.</p> </div> </mattextxml> <mattext texttype="text/html"><div class="exercise-statement"> <p> <strong>M4.</strong> </p> <p>Show how to find the inverse of the matrix <img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?M=%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D%20-3%20&amp;%201%20&amp;%20-1%20&amp;%20-1%20%5C%5C%20-1%20&amp;%200%20&amp;%200%20&amp;%201%20%5C%5C%201%20&amp;%201%20&amp;%204%20&amp;%208%20%5C%5C%20-2%20&amp;%200%20&amp;%20-2%20&amp;%20-3%20%5Cend%7Barray%7D%5Cright%5D" alt="M= \left[\begin{array}{cccc} -3 &amp; 1 &amp; -1 &amp; -1 \\ -1 &amp; 0 &amp; 0 &amp; 1 \\ 1 &amp; 1 &amp; 4 &amp; 8 \\ -2 &amp; 0 &amp; -2 &amp; -3 \end{array}\right]" title="M= \left[\begin{array}{cccc} -3 &amp; 1 &amp; -1 &amp; -1 \\ -1 &amp; 0 &amp; 0 &amp; 1 \\ 1 &amp; 1 &amp; 4 &amp; 8 \\ -2 &amp; 0 &amp; -2 &amp; -3 \end{array}\right]" data-latex="M= \left[\begin{array}{cccc} -3 &amp; 1 &amp; -1 &amp; -1 \\ -1 &amp; 0 &amp; 0 &amp; 1 \\ 1 &amp; 1 &amp; 4 &amp; 8 \\ -2 &amp; 0 &amp; -2 &amp; -3 \end{array}\right]">.</p> </div> </mattext> </material> <response_str ident="response1" rcardinality="Single"> <render_fib> <response_label ident="answer1" rshuffle="No"/> </render_fib> </response_str> </presentation> <itemfeedback ident="general_fb"> <flow_mat> <material> <mattextxml> <div class="exercise-answer"> <h4>Partial Answer:</h4> <p style="text-align:center;"> <img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?M^{-1}= \left[\begin{array}{cccc} -2 & -3 & 2 & 5 \\ -2 & -5 & 3 & 7 \\ 5 & 6 & -5 & -13 \\ -2 & -2 & 2 & 5 \end{array}\right]" alt="M^{-1}= \left[\begin{array}{cccc} -2 & -3 & 2 & 5 \\ -2 & -5 & 3 & 7 \\ 5 & 6 & -5 & -13 \\ -2 & -2 & 2 & 5 \end{array}\right]" title="M^{-1}= \left[\begin{array}{cccc} -2 & -3 & 2 & 5 \\ -2 & -5 & 3 & 7 \\ 5 & 6 & -5 & -13 \\ -2 & -2 & 2 & 5 \end{array}\right]" data-latex="M^{-1}= \left[\begin{array}{cccc} -2 & -3 & 2 & 5 \\ -2 & -5 & 3 & 7 \\ 5 & 6 & -5 & -13 \\ -2 & -2 & 2 & 5 \end{array}\right]"/> </p> </div> </mattextxml> <mattext texttype="text/html"><div class="exercise-answer"> <h4>Partial Answer:</h4> <p style="text-align:center;"> <img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?M%5E%7B-1%7D=%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D%20-2%20&amp;%20-3%20&amp;%202%20&amp;%205%20%5C%5C%20-2%20&amp;%20-5%20&amp;%203%20&amp;%207%20%5C%5C%205%20&amp;%206%20&amp;%20-5%20&amp;%20-13%20%5C%5C%20-2%20&amp;%20-2%20&amp;%202%20&amp;%205%20%5Cend%7Barray%7D%5Cright%5D" alt="M^{-1}= \left[\begin{array}{cccc} -2 &amp; -3 &amp; 2 &amp; 5 \\ -2 &amp; -5 &amp; 3 &amp; 7 \\ 5 &amp; 6 &amp; -5 &amp; -13 \\ -2 &amp; -2 &amp; 2 &amp; 5 \end{array}\right]" title="M^{-1}= \left[\begin{array}{cccc} -2 &amp; -3 &amp; 2 &amp; 5 \\ -2 &amp; -5 &amp; 3 &amp; 7 \\ 5 &amp; 6 &amp; -5 &amp; -13 \\ -2 &amp; -2 &amp; 2 &amp; 5 \end{array}\right]" data-latex="M^{-1}= \left[\begin{array}{cccc} -2 &amp; -3 &amp; 2 &amp; 5 \\ -2 &amp; -5 &amp; 3 &amp; 7 \\ 5 &amp; 6 &amp; -5 &amp; -13 \\ -2 &amp; -2 &amp; 2 &amp; 5 \end{array}\right]"> </p> </div> </mattext> </material> </flow_mat> </itemfeedback> </item>