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Homework Help: More limits

  1. Sep 25, 2010 #1
    1. The problem statement, all variables and given/known data
    lim (x->0) of (x - Sinx) / x^3

    2. Relevant equations

    3. The attempt at a solution
    I would like to know the proper route for analyzing that question... the text is saying i should end up with 1/6 ...however I'm not sure how they arrived at that answer ...
  2. jcsd
  3. Sep 25, 2010 #2
    Are you familiar with l'hopitale's rule?

    if lim (x->0) a/b = 0/0 or infinity/infitity then lim (x->0) a/b = lim (x->0) a'/b'
  4. Sep 25, 2010 #3
    not familiar with that yet ....
  5. Sep 25, 2010 #4


    Staff: Mentor

    Another approach is to replace sin x by a few terms of its Maclaurin series, but if you don't know L'Hopital's Rule, you probably don't know anything about series yet, either. Short of those two techniques, I can't think of anything else that would work for you.
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