It depends on where you want to have x2y3.
Anywhere you have formatting available, you can use \( and \) to enclose LaTeX statements.
This Question Stem
Classify this expression \( x^2 y^3 \)
looks like this after you save the question.
The spaces I put in there are optional and just to make it look nicer here.
For the category description and the answers, you do not have the content editor available to you and the \( \) trick does not work. If you try it, it just shows what you typed.
One trick you can use is Unicode characters for the superscripts. How to enter these vary by operating system and I frequently either 1) Google it and then copy/paste or 2) go into Word, Insert > Symbols to find the ones I want, and then copy/paste from Word.
The Unicode superscripted numebrs do not look as good as a superscript or subscript. In this image, I've used LaTeX, Unicode, and HTML superscripts respectively to create the three expressions.
Of those, only the middle one is available for the category description and the answers.
