## Examples 5.3.2(b):

Why these ads ...

Is the set [-1, 1] connected or disconnected ?

Back

It seems obvious that this set is connected. How should we even try to split it into
two disjoint pieces whose union gives back the original set ? But, try to prove it !
You will find that it is much easier to show that a set is disconnect than it is to
show that a set is connected.