THIS IS A TEST OF LaTeX    $ e=m c^2 $

$$\begin{pmatrix}
a_{11} & \cdots & a_{1n}\\
\vdots & \ddots & \vdots\\
a_{m1} & \cdots & a_{mn}
\end{pmatrix}$$

HOW TO USE?

Add

<script src="//cdn.bootcss.com/mathjax/2.7.0/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>

to your html files.

and use

 $..(LaTeX code)..$ or $..(LaTeX code)..$ 

to enable display.

Refer to this link

前端整合MathjaxJS的配置笔记

Thanks to DR.Donald  and Leslie Lamport！

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