### Math

MultiMarkdown 2.0 used ASCIIMathML to typeset mathematical equations. There were benefits to using ASCIIMathML, but also some disadvantages.

When rewriting for MultiMarkdown 3.0, there was no straightforward way to implement ASCIIMathML which lead me to look for alternatives. I settled on using MathJax. The advantage here is that the same syntax is supported by MathJax in browsers, and in LaTeX.

This does mean that math will need to be entered into MultiMarkdown documents using the LaTeX syntax, rather than ASCIIMathML.

To enable MathJax support in web pages, you have to include a link to an active MathJax installation — setting this up is beyond the scope of this document, but it’s not too hard.

Here’s an example of the metadata setup, and some math:

latex input:    mmd-article-header
Title:          MultiMarkdown Math Example
latex input:    mmd-article-begin-doc
latex footer:   mmd-memoir-footer
src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
</script>

An example of math within a paragraph --- \$${e}^{i\pi }+1=0\$$
--- easy enough.

And an equation on it's own:

\${x}_{1,2}=\frac{-b\pm \sqrt{{b}^{2}-4ac}}{2a} \$

That's it.


Here’s what it looks like in action (if you’re viewing this document in a supported format):

An example of math within a paragraph — $${e}^{i\pi }+1=0$$ — easy enough.

And an equation on it’s own:

${x}_{1,2}=\frac{-b\pm \sqrt{{b}^{2}-4ac}}{2a}$

That’s it.

In addition to the \$\$ and \$$\$$ syntax, you can use LaTeX style “dollar sign” delimiters:

An example of math within a paragraph --- ${e}^{i\pi }+1=0$
--- easy enough.

And an equation on it's own:

$${x}_{1,2}=\frac{-b\pm \sqrt{{b}^{2}-4ac}}{2a}$$

That's it.


In order to be correctly parsed as math, there must not be any space between the \$ and the actual math on the inside of the delimiter, and there must be space on the outside.

### Superscripts and Subscripts

You can easily include superscripts and subscripts in MultiMarkdown as well:

This apartment has an area of 100m^2
One must consider the value of x~z


becomes

This apartment has an area of 100m2
One must consider the value of xz

The subscript must not contain any whitespace or punctuation.

More complicated exponents and subscripts can be delimited like this:

y^(a+b)^
x~y,z~


y(a+b)
xy,z