Good question Zac, 
If you look in the "Insert" drop down list, the second last one is "special characters"
The √ is in t he 3rd row some of the indices are in there as well.
I was expecting to find pi in there but I cannot see it. 
Now go to the fromat dropdown list. There are all sorts of formating things in there including superscripts (powers) and subscripts. If I was not using LaTex that is what I would use for powers.
If I wanted pi I would open up the [Math Formula] box and type in pi and hit Ok:)
Does that cover it ?
I see MG has given you LaTex solutions. I have given you non-LaTex solutions :)
oh, in latex pi is just \pi