A Tiny MCE plugin which makes writing latex equation easy and WYSIWYG（what you see is what you get）. It converts latex code into image which shows real beautiful latex equations on your post.
It adds an “fx” botton on the wordpress TinyMCE editor, on clicks it the codecogs latex equation editor pops up, where you can edit latex, then click the copy button to copy the equation image back in TinyMCE textarea.
You can also use this editor to only input latex code and let plugins like quicklatex, mathjax or Latex for WordPess to convert it to equation image, you’d better change line 90 in editor_plugin.js 
tinyMCE.activeEditor.execCommand(‘mceInsertContent’, false, ”); 
to 
tinyMCE.activeEditor.execCommand(‘mceInsertContent’, false, ‘\[‘+latex+’\]’); 
inorder to only copy LaTex code to TinyMCE textarea when click the copy button.
I just followed the tutorial written by Greg Winiarski(http://ditio.net/2010/08/15/adding-custom-buttons-to-wordpress-tinymce/) and make codecogs Tiny MCE plugin(http://www.codecogs.com/latex/integration/tinymce/install.php) into a wordpress plugin. Thanks the great guys. If you can make the plugin better to use please tell me in http://www.verymath.com/2011/05/10/codecogs-latex-equation-editor/
<h3>Arbitrary section</h3>
You may provide arbitrary sections, in the same format as the ones above. This may be of use for extremely complicated 
plugins where more information needs to be conveyed that doesn’t fit into the categories of “description” or 
“installation.” Arbitrary sections will be shown below the built-in sections outlined above.
<h3>A brief Markdown Example</h3>
Ordered list:
<ol>
<li>Some feature</li>
<li>Another feature</li>
<li>Something else about the plugin</li>
</ol>
Unordered list:
<ul>
<li>something</li>
<li>something else</li>
<li>third thing</li>
</ul>
Here’s a link to <a href="https://wordpress.org/" title="Your favorite software" rel="ugc">WordPress</a> and one to <a href="http://daringfireball.net/projects/markdown/syntax" title="Markdown is what the parser uses to process much of the readme file" rel="nofollow ugc">Markdown’s Syntax Documentation</a>. 
Titles are optional, naturally.
Markdown uses email style notation for blockquotes and I’ve been told:
<blockquote>
Asterisks for emphasis. Double it up for strong.
</blockquote>
<pre><code><?php code(); // goes in backticks ?>
</code></pre>

Codecogs Latex Equation Editor

Adds codecogs WYSIWYG LaTex equation popup editor to wordrpess TinyMCE editor.

Terry L.

WP MathJax displays mathematical notation in web browsers, using MathML, LaTeX and ASCIIMath markup on WordPress by using MathJax.js.
WP MathJax is smart enough that loads mathjax.js only when your posts contain mathjax syntax, by detecting the use of shortcode and block. So it will not be loaded on your website everywhere.
If you are not using Guteberg editor and looking for a <a href="https://github.com/terrylinooo/githuber-md" rel="nofollow ugc">Markdown editor</a> supporting MathJax, you can also check out my WordPress plugin called the WP Githuber MD, which provides a variety of features not just MathJax, it is worth to try.
<h3>Copyright</h3>
WP MathJax, Copyright 2020 TerryL.in 
WP MathJax is distributed under the terms of the GNU GPL
This program is free software: you can redistribute it and/or modify 
it under the terms of the GNU General Public License as published by 
the Free Software Foundation, either version 3 of the License, or 
(at your option) any later version.
This program is distributed in the hope that it will be useful, 
but WITHOUT ANY WARRANTY; without even the implied warranty of 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
GNU General Public License for more details.

WP MathJax

WP MathJax displays mathematical notation in web browsers, using MathML, LaTeX and ASCIIMath markup on WordPress by using MathJax.js.

Codecogs Latex Equation Editor vs WP MathJax