Well, trivial or not, there's a difference between asking a research question and asking that exact question as an exercise from a textbook. The latter presumably wants an answer drawing from ideas of the chapter that it's in, whereas the former would (in the spirit of MO questions) allow any sort of valid solution as an answer. So I see Mariano's point -- plus, MO doesn't want to be a "solve grad student's homework" site, even if they are interesting questions. That said, I'm now interested in the problem, and if I don't get it by this afternoon, will probably be ready for an answer...

Oh, and Lars -- yup, plenty of LaTeX support. There are several bots you can invite to your conversation that will automatically convert tex code -- some real-time and some after you submit. I've tried several, and by far my current favorite is [email protected] (just invite that bot to your conversation). Anyone have a better one?

Agreed. I use it for collaboration, but only for bouncing ideas off of a collaborator and keeping a log of these ideas, not for the actual writing of the paper. (ScribTex above looks promising for that aspect). Think of it as half-way between instant messaging and email.

Almost certainly. Good point.