I am a little confused here:(adsbygoogle = window.adsbygoogle || []).push({});

a) The number 2 which is at the beginng of one set is closed.

The number 2 is open at the beginning of the other set.

b) The number 2 is closed of the beginning of a set which goes to infinity.

The other set begins at 0 and goes to infinity (2 is an element of the set).

How is closed 2 handled in the interaction and union of the sets in a and b?

Another way of asking these questions is how do the line intervals look like?

Thanks,

Confused,

Arthur Rupel

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# I Intersection & union of closed and open sets?

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