If it has generated a response, then I don't think you should delete them. For one thing: once you demonstrate that you are willing to remove you question, and hence the answers given, from the public record, people will be less willing to take their time to help you in the future. One of the great things about MO is that it is a repository of questions and answers. The questions may no longer be useful to you personally, but it may still be so in the future for someone else.

Besides, as Doron Zeilberger is wont to say: "there are no trivial mathematical questions, only trivial mathematicians." So don't be ashamed at the questions you asked: if you feel more enlightened now then you were before, you should be happy that you've grown mathematically.

+1 Alex.

@Max: If it makes you feel better, you can always edit the question to have something like "Ah, I see this was easy, but I'll leave it here for posterity's sake." Then you get to acknowledge it was easy, but don't remove anyone's hard work. But, to emphasize Alex's point, this is completely unnecessary. Probably a good 2/3s of the questions with accepted answers on the site made the asked feel like an idiot in hindsight -- that doesn't mean they were bad questions. On top of that, being okay feeling liking an idiot is one of the most important skills to develop. I consider myself particularly skilled on that front.

On top of that, being okay feeling liking an idiot is one of the most important skills to develop.

Couldn't agree more! I do my level best to ensure that my students get every opportunity to learn this.

(I suspect that I ought to qualify that to ensure that it's not taken the wrong way, but I'm not sure whether to say that it's the students who feel like idiots or me who feels like an idiot - I suspect that I'll get keelhauled for Encouraging Bad Teaching Again either way.)

Whatever, I'm adding my support to the "don't delete old questions just because you don't like 'em anymore" party.

(JBL: your comment is where that parenthetical remark stems from, but I have no particular axe to grind. In that particular proto-discussion, I suspect that were you, Mark, Sean, and I to meet in a pub and have the same discussion we'd all conclude that we have the same views. Indeed, your comment and the responses ensure that no-one is left in any doubt that we aren't cheerleading Bad Teaching. But although that's where my cry of "Let's support Bad Teachers" began, I've found so many more uses for it that I'm afraid you can't claim ownership any more. For one thing, I use it as a way to ensure that everyone knows I'm being a bit tongue-in-cheek - after all, no-one would actually publicly advocate Bad Teaching, would they? That's not to say that I wouldn't happily continue the discussion - I would love to hear of and learn from others' experiences of teaching maths - but I fear that the place to have such a discussion does not yet exist: neither here nor MO is suitable. Mind you, the technology exists so if you want to have that discussion, I could build a Maths Pub in about five minutes. Fancy a pint?)

Andrew: I'm certainly glad you got a useful slogan out of it, but after seeing you bring it up a few times I feel I owe you an apology for making the comment that started that proto-discussion.

Finally, as a technical matter, the moderators can delete questions that the software won't allow the original poster to, and if there is some unusual circumstance meriting deletion you should contact us, here or via email.