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I'm an 3rd year undergraduate student, and this semester, I'm taking graduate course in one of my departments.
We have homeworks each week, and while doing the problems on those, I sometimes get stuck. In that case, sometimes I go to the instructor for some hints and discussions, and sometimes, if I really haven't made any progress in that question for long time, I search the answer onthe web (for example math.SE), and write that answer if it satisfies me.
In those latter cases, I put some notes/a disclaimer on the top of the question stating that "I've done these and these, but couldn't solve it, so I looked at the answer from the xxx website".
However, is this something that we indeed expected to do, or am I just making myself sometimes look like "incapable of solving even an elementary question" in the eyes of my instructor ?
Edit: My question is about the general norm in academia, not whether it is considered cheating or not.