This is LaTeX code:

[latex]
\vec a \times \vec b = \left[\begin{array}{ccc}
0&-a_3&a_2\\
a_3&0&-a_1\\
-a_2&a_1&0
\end{array}\right]\left[\begin{array}{ccc}
b_1\\
b_2\\
b_3
\end{array}\right]
[/latex]