Q: What is the proper way to respond to homework questions on math.stackexchange?
A:
Consider the guidelines given for askers of homework questions. If the question apparently lacks previous work or thought behind it, consider requesting a revision that follows these guidelines more closely.
Give the question asker a chance to respond before voting to close.
Providing an answer that doesn't help a student learn is not in the student's own best interest, and if a solution complete enough to be copied verbatim and handed in is given immediately, it will encourage more people to use the site as a free homework service. In the spirit of creating a lasting resource of mathematical knowledge, you may come back after a suitable amount of time and edit your response to include a more complete answer. Or even better, the student can post her or his own correct answer!
It's much better to give a hint, so that the asker may find the right direction.
It is encouraged to suggest other problems that use the same principles or techniques. Parallel problems are a great teaching tool.
Don't downvote others who provide complete answers to questions just because you think it might be homework. It's not always obvious at first glance that a question is homework, especially when you're not expecting to see it. Instead, suggest editing the response in a comment.
On the other hand, do feel free to downvote overly complete answers to known homework (as in, you know that this instance of the question is homework) if you think the asker has not done enough to 'deserve' it.
Don't ridicule a student because they haven't yet learned something obvious.
Be polite and encouraging! Nothing makes people hate math more than having smart people tell them they suck at it.
Related: http://meta.math.stackexchange.com/questions/106/what-is-the-proper-way-to-handle-homework-questions
http://meta.stackexchange.com/questions/10811/how-to-ask-and-answer-homework-questionshttps://meta.stackexchange.com/questions/10811/how-to-ask-and-answer-homework-questions
http://meta.math.stackexchange.com/questions/415/homework-questions-avoiding-giving-a-complete-solution