Mistake in my analysis book ? Or am I missing something ?

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Homework Statement



Please review the attachment.

Why can L be OUTSIDE of D ?

x_n \in D and D is bounded. So doesn't that mean that any subsequential limit of x_n 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.
 

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I think I understand now.

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

x_{n_k} \to a 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.
 
Perfect. Thanks.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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