This is just an article for testing MathJax in Markdown files.
You can use this as a testing template for all of your LaTeX math needs.
Basics
This should be an inline math content \(\LaTeX\) with the LaTeX symbol.
The following block content should contain a sentence with the LaTeX symbol.
$$\LaTeX\text{ is awesome.}$$
Whitespace
LaTeX treats whitespace characters such as tabs and spaces uniformly as one unit of space. A text that is composed of two tabs and 10 spaces consecutively is one space.
This is especially prominent in math mode (which MathJax is… always).
Try to render this, for example.
This is a LaTeX sentence (or I guess in MathJax).
And it’ll render as the following:
$$ This is a LaTeX sentence (or I guess in MathJax). $$
Since MathJax is in… perpetual math mode and specifically made for rendering math formulae, we shouldn’t have a problem with maintaining it.
Just a heads up.
Commands
One of the main syntax you should mind in MathJax are the LaTeX commands. Think of it like the HTML tags in LaTeX (although not really).
Here’s the basic construct of a LaTeX command:
\commandname[option1,option2,...]{argument1}{argument2}...
Within commands and if allowed, you can nest commands. Take this example for example:
\sum_{i=0}^{6} = \frac{i^{2}}{ 2 \bmod (i * 4)} + i^{3}
$$ \sum_{i=0}^{6} = \frac{i^{2}}{ 2 \bmod (i * 4)} + i^{3} $$
Reserved characters
The following characters have special meaning to LaTeX.
# $ % ^ & _ { } ~ \
$$ # $ % ^ & _ { } ~ \ $$
As you can see, if rendered, it should result in an error.
In order to render them in text, you need to add an escape character. In this case, it’s a backslash.
\# \$ \% \^ \& \_ \{ \} \~ \\
In the case of rendering it from Markdown, double slashes might be needed.
$$ \# \$ \% \^ \& \_ \{ \} \~ \ $$
Text formatting
You can do a little text formatting in a LaTeX math content (though it’s pointless to do so).
Literal text
You can make a text with \text{}.
\text{The quick brown fox jumps over the lazy dog.}
$$\text{The quick brown fox jumps over the lazy dog.}$$
Boldface text
You can make a text boldface with \textbf{}.
\textbf{The quick brown fox jumps over the lazy dog.}
$$\textbf{The quick brown fox jumps over the lazy dog.}$$
Italic text
To make a text block italic, enclose it with a \textit{} command.
\textit{The quick brown fox jumps over the lazy dog.}
$$\textit{The quick brown fox jumps over the lazy dog.}$$
Monospaced text
In order for the text to be monospaced, enclose it with a \texttt{} (text teletype) command.
\texttt{The quick brown fox jumps over the lazy dog.}
$$\texttt{The quick brown fox jumps over the lazy dog.}$$
Text in sans-serif font equivalent
Most importantly, you can make a text rendered in sans-serif with \textsf{} command.
\textsf{The quick brown fox jumps over the lazy dog.}
$$\textsf{The quick brown fox jumps over the lazy dog.}$$
More options
You can see a lot more options from this reference.
Math formatting
This is what you mostly came for, right?
All righty then. Let’s see what MathJax in Markdown (M in M?) can do.
Fractions
For rendering fractions, you need to use the \frac command.
The command simply needs two positional arguments.
\frac{NUMERATOR}{DENOMINATOR}
For a bit of an example:
\frac{x_1 + y_2}{x_2 + y_1}
$$ \frac{x_1 + y_2}{x_2 + y_1} $$
Roots
In order to create roots, you need the \sqrt command.
It only needs the content to be put inside of it as the argument.
\sqrt{2a + b}
$$ \sqrt{2a + b} $$
Yes, you can nest some stuff.
\sqrt{\frac{2a + b}{a^2 - b^2}}
$$ \sqrt{\frac{2a + b}{a^2 - b^2}} $$
You can specify an optional argument to change the magnitude.
\sqrt[\frac{1}{2}]{2a + b}
$$ \sqrt[\frac{1}{2}]{2a + b} $$
Superscripts
In order to make superscripts, place it next to a caret character (^).
To render it in more than one character, enclose it in curly brackets ({}).
2^2 * 2^{23} = 2^{25}
$$2^2 * 2^{23} = 2^{25}$$
You can also nest it within a superscript like so.
2^{2^{10}} * 2^{23^2} = \infty
$$ 2^{2^{10}} * 2^{23^2} = \infty $$
OK, I’ve gone overboard with the scale so I just put infinity as the answer instead.
Subscripts
For making subscripts, place it next to the underscore (_).
Like the superscript command, if you include more than one character,
enclose it in a pair of curly brackets ({}).
a_1 + a_2 + a_3 + ... + a_{14} = \frac{a_1 * a_{14}}{2}
$$ a_1 + a_2 + a3 + … + a{14} = \frac{a1 * a{14}}{2} $$
Wait… That doesn’t look right.
That’s because in Markdown, underscores denote italics so be sure to escape them with a single backslash.
So now, the result is this:
a\_1 + a\_2 + a\_3 + ... + a\_{14} = \frac{a\_1 * a\_{14}}{2}
$$ a_1 + a_2 + a_3 + … + a_{14} = \frac{a_1 * a_{14}}{2} $$
Like superscripts and most of the commands, you can nest subscripts to another subscript (and other commands).
a\_{2\_{1}} + a\_{2\_{2}} = b\_{2\_{1}} + b\_{2\_{2}}
$$ a_{2_{1}} + a_{2_{2}} = b_{2_{1}} + b_{2_{2}} $$
Greek letters
You can render Greek letters with the appropriate command.
\alpha for lowercase Greek letter alpha,
\beta for lowercase Greek letter beta,
\gamma for lowercase Greek letter gamma,
\Gamma for uppercase Greek letter gamma,
you get the point.
\alpha, \beta, \gamma, \Gamma, \pi, \Pi, \phi, \varphi, \mu, \Phi
$$\alpha, \beta, \gamma, \Gamma, \pi, \Pi, \phi, \varphi, \mu, \Phi$$
A lot more!
You have a whole slew of mathematical symbols available. Please refer to this list of LaTeX mathematical symbols. Though I don’t know what’s missing symbols and whatnot (since I don’t MathJax often) but it should be enough.
You can also go to this web page that details using MathJax on Quora by Gilles Castel. It is specifically made for writing \(\LaTeX\) on Quora but it can be used as a general MathJax guide, anyways.