This is not about solving homework questions per-se. Several questions of the type "How do I solve for this probability density" can be solved by the Jacobian method (change of variables) but most answers even the ones most voted usually just present a particular solution that addresses only the question at hand. Whenever I assign homework with such questions my intent was always for students to learn the general method. In sum: here should we give them fish or should we teach them how to fish?
One possibility is to either answer one such question in full generality or ask-and-answer yourself one such question, and then tagging it with faq and adding the question to this list. After which you can always refer to that item when you see another such question where the general technique applies.