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Homework Help: Determining Limits

  1. Apr 6, 2010 #1
    1. The problem statement, all variables and given/known data
    Determine the limit as x approaches 0 of

    f(x) = [(1+x)1/2 - 1] / [(1+x)1/3 - 1]

    2. Relevant equations
    I am not allowed to use L'Hopital's Rule.

    3. The attempt at a solution
    I multiplied by the conjugate of the numerator and got a nasty denominator that I cannot simplify nicely. Can someone give me a lead?
  2. jcsd
  3. Apr 6, 2010 #2
    May you use taylor series?
  4. Apr 6, 2010 #3
    I just found out that I should multiply by an expression to get a sum of cubes (totally forgot about that). =P

    (Thread can be closed now.)
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