1) give an example of a sequence (An) of open sets such that the intersetion(adsbygoogle = window.adsbygoogle || []).push({});

∩ An is not open.

n in N

2) If A is a nonempty set of real numbers bounded below with no minumum, then infA is an accumulation point of A.

Could somebody gives some hint on those questions? Thank you very much...i have no i dear on the 2nd prove....

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# Help : on accumulation point

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