# Mathematics

To enable LaTeX syntax for maths:

1. Make sure mathjax-enabled: true is set in _config.yml. It may be off (false) to avoid loading unnecessary scripts in books without maths.
2. For PDF output, you must have installed Node, and have run the ‘Install and update dependencies’ option in the output script. (This is because the maths must be rendered before Prince can include it in PDF output.)

The LaTeX is turned into displayed maths by MathJax. Surround your LaTeX with $$$$ to have MathJax process it.

## MathJax in HTML blocks

Sometimes you have to use actual HTML code in your markdown, for instance when adding an HTML table to a figure include. In that case, surround LaTeX with $$$$ for displayed maths (centered, with blank space above and below), and $$$$ for inline maths.

## Avoid using LaTeX for content layout

LaTeX syntax can store two different kinds of info:

1. mathematics, delimited in our markdown with 
2. content layout, which must not be used with MathJax.

MathJax can only display the mathematics, and does not understand content layout. (More detail here.)