Exercise 4

Find the inverse, if it exists, by using the Gauss-Jordan Method. Check the answers for the $2\!\times\!2$ matrices with Corollary 4.11.

• (a)  $\begin{pmatrix}3&1\\ 0&2\end{pmatrix}$     (b)  $\begin{pmatrix}2&1/2\\ 3&1\end{pmatrix}$     (c)  $\begin{pmatrix}2&-4\\ -1&2\end{pmatrix}$     (d)  $\begin{pmatrix}1&1&3\\ 0&2&4\\ -1&1&0\end{pmatrix}$     (e)  $\begin{pmatrix}0&1&5\\ 0&-2&4\\ 2&3&-2\end{pmatrix}$     (f)  $\begin{pmatrix}2&2&3\\ 1&-2&-3\\ 4&-2&-3\end{pmatrix}$