Click on your MathForm bookmark to make sure you have the latest version (be6e436ca1).
MathForm is a simple mashup to add mathematical formula input to online forms.
Drag this link to your bookmarks,
and use it on Google Forms that support MathForm. (Demo)
Division: Type a/b. Then tab to get out of the denominator.
Create a MathForm
Follow these instructions to start using MathForm in Google Forms.