LaTeX plugin test

This post is just to test the WP latex plugin

[latex] x^Tunderbrace{mathbf{Q} }_{text{symmetric}} x =2sum_i \sum_j x_i x_j Q_{i,j}[/latex]

It works! but the \mathbbm command (to make blackboard bold fonts with numbers) does not work.

It is used putting the [latex]LaTeX[/latex] code inside [ latex ] [ /latex ] (without the blanks)