# How to write augmented matrix in LeTex?

Here is the LeTex code.

`\left[`

\begin{matrix}

1 & 2 & 3 \\

1 & 2 & 3 \\

1 & 2 & 3

\end{matrix}

\left|

\,

\begin{matrix}

4 \\

4 \\

4

\end{matrix}

\right.

\right]

The output is: