One of the WordPress drawbacks is lack of default support of math formulas. Fortunately, there are few plugins available to facilitate adding LaTeX style equations. Among them, WP QuickLaTeX and Jetpack by WordPress.com plugins seem to work the best. Simply just install one of them and add your equation in any sechttp://blog.madadipouya.com/wp-admin/post-new.phption of post as follows:
The output is this.
Personally, I have found writing LaTeXequations without any visual tool cumbersome.
Happily Codecogs is available for such a task which alleviates much of the pain. It works perfectly fine, just write your equations and then cut/paste to WordPress.