Exercise 3

Find the reduced echelon form of each matrix.

• (a)  $\begin{pmatrix}2&1\\ 1&3\end{pmatrix}$     (b)  $\begin{pmatrix}1&3&1\\ 2&0&4\\ -1&-3&-3\end{pmatrix}$     (c)  $\begin{pmatrix}1&0&3&1&2\\ 1&4&2&1&5\\ 3&4&8&1&2\end{pmatrix}$     (d)  $\begin{pmatrix}0&1&3&2\\ 0&0&5&6\\ 1&5&1&5\end{pmatrix}$