(adsbygoogle = window.adsbygoogle || []).push({}); question about the set [a,a)

If S=[a,a) Can such a set exist? It implies that a is in S and not in S, which doesn't make sense, but it seems a problem I'm trying to do requires it to be considered empty.

The question is:

Let I_{n}= [a_{n},b_{n}) where

I_{n+1}< I_{n}for all natural numbers n. [< denotes subset]

Give an example of those I_{n}for which the intersection of I_{n}(for all n) is empty.

I can't see any other way to construct an empty set.

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# Homework Help: Question about the set (a,a]

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