expert kisu noi, I've used it that's all.
here's an example using http://www.codecogs.com/latex/eqneditor.php
here is the input code
\int^b_a dx = [x]^b_a = b-a
you can also go the whole hog and do everything in latex instead of OO but it takes a few days of getting used to. the good thing is you have complete control over the environment.