Can you use packages on math.stackexchange?
The help associated with the editor does not mention packages, so I am guessing it's not possible.
But if it is, how? I am particularly interested in the centernot package at the moment.
If there is documentation or a prior question for this, please direct me to it -- I have searched for this answer with no luck. There are responses on package use on tex.stackexchange, but they do not work as-is on stackexchange.
Finally, is this a good place to ask questions about TeX usage in stackexchange? When I tried such a question on meta.math.stackexchange, I got scolded and sent here. Well, it was a generic TeX question, and this one is specific to stackexchange.