Hi! I put up an "intro post" a while back, can't find it anymore. I'm hoping somebody can help me with a simple (I assume) problem, not in math, but in using this forum.

How do I enter mathematical notation? I can see a button I can for a subscript or superscript, but I don't know how to put in a radical for a square root, or a top-and-bottom fraction, let alone an integral sign. How do I do that kind of stuff?

A thousand pardons if this isn't the right place to ask such a question, but I don't know where else to put it.