Matrices

The amsmath package provides commands for typesetting matrices with different delimiters. Once you load \usepackage{amsmath} in the preamble, you can use the following environments in mathematical contexts.

Quick Reference:

\begin{matrix}
1 & 2 & 3\\
a & b & c
\end{matrix}

\begin{pmatrix}
1 & 2 & 3\\
a & b & c
\end{pmatrix}

\begin{bmatrix}
1 & 2 & 3\\
a & b & c
\end{bmatrix}

\begin{Bmatrix}
1 & 2 & 3\\
a & b & c
\end{Bmatrix}

\begin{vmatrix}
1 & 2 & 3\\
a & b & c
\end{vmatrix}

\begin{Vmatrix}
1 & 2 & 3\\
a & b & c
\end{Vmatrix}

\left\lceil
\begin{matrix}
1 & 2 & 3\\
a & b & c
\end{matrix}
\right\rceil

\left\langle
\begin{matrix}
1 & 2 & 3\\
a & b & c
\end{matrix}
\right\rvert

\left\langle
\begin{matrix}
1 & 2 & 3\\
a & b & c
\end{matrix}
\right\rangle

Inline Matrices

When typesetting inline mathematics, the regular matrix environments above may appear too large. In such cases, using smallmatrix might be better, although you need to provide your own delimiters.

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\noindent Trying to typeset an inline matrix here:
 $\begin{pmatrix}
  a & b\\ 
  c & d
\end{pmatrix}$,  
but it looks too big, so let's try 
$\big(\begin{smallmatrix}
  a & b\\
  c & d
\end{smallmatrix}\big)$ 
instead.
\end{document}