Sometimes I am really surprised how fast are the duplicates of new question found, given that we have vast amount of questions here.
I hope posting this question here can be useful and can lead to some constructive suggestions. If it was discussed here before and I've overseen it, my apologies. (It would be, however, a little ironic.)
A few methods for finding duplicates that come to mind are the following:
- Look in the list of related questions, which is generated automatically.
- Sometimes it is useful to look in this list: http://meta.math.stackexchange.com/questions/1868/list-of-generalizations-of-common-questions Another useful list is mentioned in this post: http://meta.math.stackexchange.com/questions/16708/catalog-of-standard-exercises
- If you remember that you posted such question/commented such question/answered such question, it might be relatively easy to find it in your list of comments/answers/questions.
- Even if you only remember seeing such a question, it might make your life easier - you can remember poster, part of the title, a phrase used in the answer, simply something which helps you find the question more quickly.
- You might search for the question - either here or using google. This might be not that easy if the search would involve mathematical formula, but:
- If the formula has a name, it is probably mentioned in the answer or in the comments, so you might try to search for the name, e.g. "triangular number" site:math.stackexchange.com on google or triangular number on MSE. (The search on google has the advantage that it also looks into comments.)
- If you know the correct result, you can search for some part of formula e.g "frac n(n+1)2" or "n(n+1) 2" site:math.stackexchange.com on google or here. However, the search for "n(n-1)/2", "k(k+1)/2" or "s(s+1)/2" might be reasonable in this case, too. (In general, it is not easy to search for formulas.)
- If it is a question which was probably asked many times on Math.SE, you can try your luck on the frequent tab, which shows the questions with most links. (Perhaps it is useful to restrict this to some particular tag, like here.)
Are there some other useful tricks to find the duplicates?