Can a subsequential limit be outside a bounded closed set?

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Homework Statement



Please review the attachment.

Why can L be OUTSIDE of D ?

[tex]x_n \in D[/tex] and D is bounded. So doesn't that mean that any subsequential limit of [tex]x_n[/tex] has to be in D ? Btw, Theorem 3.10 is Bolzano Weierstrass.
Theorem 4.4 Says that A continuous function on a closed interval is uniformly continuous there.
 
Attachments
  • Printed textbook page showing Theorem 4.6 and its proof on uniform continuity of f on a bounded set D, with a handwritten underline under the note that L may or may not be in D.
    DSC_0025.jpg
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Last edited:
I think I understand now.

They said that D is bounded by not closed. i.e suppose D = (a,b)

[tex]x_{n_k} \to a[/tex] could happen and a in not in D.

Is this correct ? Anyone ?
 
What you said is right. Also, the bounded subset need not be an interval of reals; for example, the subset could be all the rational numbers from 0 to 2. Then there are an uncountable number of points not in the set that are the limit of Cauchy sequences inside the set.