Question

Please help if you can pic attatched

Answer 1

Explanation:

`CI=\left[\begin{array}{ccc}1&6&0\\0&1&2\\1&-1&3\end{array}\right] \left[\begin{array}{ccc}1&0&0\\0&1&0\\0&0&1\end{array}\right]`

Subtract row 3 from row 1:

`\left[\begin{array}{ccc}1&6&0\\0&1&2\\0&7&-3\end{array}\right] \left[\begin{array}{ccc}1&0&0\\0&1&0\\1&0&-1\end{array}\right]`

Subtract row 3 from 7 times row 2:

`\left[\begin{array}{ccc}1&6&0\\0&1&2\\0&0&17\end{array}\right] \left[\begin{array}{ccc}1&0&0\\0&1&0\\-1&7&1\end{array}\right]`

Divide row 3 by 17:

`\left[\begin{array}{ccc}1&6&0\\0&1&2\\0&0&1\end{array}\right] \left[\begin{array}{ccc}1&0&0\\0&1&0\\(-1)/(17) &(7)/(17) &(1)/(17) \end{array}\right]`

Subtract 2 of row 3 from row 2:

`\left[\begin{array}{ccc}1&6&0\\0&1&0\\0&0&1\end{array}\right] \left[\begin{array}{ccc}1&0&0\\(2)/(17) &(3)/(17) &(-2)/(17) \\(-1)/(17) &(7)/(17) &(1)/(17) \end{array}\right]`

Subtract 6 of row 2 from row 1:

`\left[\begin{array}{ccc}1&0&0\\0&1&0\\0&0&1\end{array}\right] \left[\begin{array}{ccc}(5)/(17)&(-18)/(17)&(12)/(17)\\(2)/(17) &(3)/(17) &(-2)/(17) \\(-1)/(17) &(7)/(17) &(1)/(17) \end{array}\right]`

`C^(-1)=(1)/(17) \left[\begin{array}{ccc}5&-18&12\\2&3&-2\\-1&7&1\end{array}\right]`

`C^(-1)b=(1)/(17) \left[\begin{array}{ccc}5&-18&12\\2&3&-2\\-1&7&1\end{array}\right]\left[\begin{array}{c}10&1&3\end{array}\right]=\left[\begin{array}{c}4&1&0\end{array}\right]`