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Limit ?

  1. Apr 25, 2010 #1
    I can not understand what to do with this

    Lim 1/2^x-1 as x goes to infinity.

    i tried using l'hopitals rule but it does't work or im not applying it right.
  2. jcsd
  3. Apr 25, 2010 #2


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    You should include () to clarify.
    (1/2^x)-1 or 1/2^(x-1)
  4. Apr 26, 2010 #3


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    [itex](1/2)^x- 1[/itex] goes to -1, of course,
    [itex]1/(2^{x-1})[/itex] goes to 0.

    [tex]\frac{1}{2^x- 1}[/tex] also goes to 0. You don't need L'Hopital because the numerator does not go to infinity. The numerator is always 1 while the denominator goes to infinity.
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