Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2004/iii/paper-1/2/i/solution

If , all its localizations are zero. Conversely, take . Its annihilator is a proper ideal, so it is contained in a maximal ideal , which is prime. The zero criterion for module localization says that in only if some satisfies . This would put , a contradiction. Therefore , proving
In fact maximal ideals suffice, and neither finite generation nor Noetherianity is needed for this implication.

New to topics? Read the docs here!