mdBook has optional support for math equations through MathJax.

To enable MathJax, you need to add the mathjax-support key to your book.toml under the output.html section.

[output.html]
mathjax-support = true

Note:
The usual delimiters MathJax uses are not yet supported. You can't currently use $$ ... $$ as delimiters and the \[ ... \] delimiters need an extra backslash to work. Hopefully this limitation will be lifted soon.

Inline equations are delimited by \\( and \\). So for example, to render the following inline equation \( \int x dx = \frac{x^2}{2} + C \) you would write the following:

\\( \int x dx = \frac{x^2}{2} + C \\)

Block equations are delimited by \\[ and \\]. To render the following equation

\[ \mu = \frac{1}{N} \sum_{i=0} x_i \]

you would write:

\\[ \mu = \frac{1}{N} \sum_{i=0} x_i \\]