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Homework Help: Another convergence proof

  1. Sep 20, 2011 #1

    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.

    1. The problem statement, all variables and given/known data

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

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Sep 20, 2011 #2
    If [itex]a_n \rightarrow 0 [/itex] you know that after some n [itex]|a_n|\leq \epsilon/2[/itex]

    So what can you tell?

    Please show your attempt. [This is as close to trivial as it can be]
    Last edited: Sep 20, 2011
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