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Homework Help: Triangle inequality proof

  1. Sep 18, 2008 #1
    My professor said this was the triangle inequality. We're to use mathematical induction to prove it. I've gotten some work done, and after "proving" it, it just seems to easy. :|

    http://answerboard.cramster.com/advanced-math-topic-5-321495-0.aspx" [Broken].
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Sep 18, 2008 #2


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    Homework Helper

    The work you've done is essentially correct - the idea is to write

    |a_1 + a_2 + \dots + a_k + a_{k+1}| = |(a_1 + a_2 + \dots + a_k) + a_{k+1}|

    then use the hint once, then your induction hypothesis.
  4. Sep 19, 2008 #3
    thank you

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