Convergence Proof: |a_n| Converges to 0 if a_n Converges to 0

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Hi,

Here's another question from my analsysi HW. I get that the two sequences are equal but I'm not sure how to write it out. Any help would be great.
Thanks.

Homework Statement



Prove that a sequence {a_n} converges to 0 iff the sequence {\lvert a_n\rvert} converges to 0.

Homework Equations





The Attempt at a Solution

 
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If a_n \rightarrow 0 you know that after some n |a_n|\leq \epsilon/2

So what can you tell?

Please show your attempt. [This is as close to trivial as it can be]
 
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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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