We'll create fresh WordPress site with Youngwhan's Simple Latex installed. You have 20 minutes to test the plugin after that site we'll be deleted.
The usage is simple.
In your post, write LaTeX syntax encapsulated by [math] and [/math].
[math]{Latex Syntax}[/math].
For example, [math]x^2+y^2[/math]
It uses the Mathjax (https://www.mathjax.org) since the 2.0 version
No Setting is required.