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Homework Help: Solve this limit when x tends to +infinity

  1. Nov 21, 2006 #1
    any hints to solve this limit when x tends to +infinity is way very appreciated !!!!
    PS: i should not use the hopital rule...
    I tried to factorize the x from the nominator and denominator but couldnt get to any result... i tried some other things.. but still nothing.

    [tex]\frac{x^{\frac{2}{3}} - 3^{x}}{x^{\frac{5}{2}} + 2^{x}}[/tex]

    thanks very much
  2. jcsd
  3. Nov 21, 2006 #2


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    Rewrite this as:
  4. Nov 23, 2006 #3
    okay the limit of (3/2)^x is +infinity
    but i have to show that the limit of [tex]\frac{x^{2/3}}{3^x}[/tex] is zero... how ?? maybe I have to show that it is smaller than a number, then the limit of that number should be zero... by the way, we havent studied exponentials yet..

    PS: I think this should be moved to calculus and beyond ?
    Last edited: Nov 23, 2006
  5. Nov 23, 2006 #4


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    the limit of [tex]\frac{x^{2/3}}{3^x}[/tex] goes to zero.

    EDIT: Latex is so texy :rofl:
    Last edited: Nov 23, 2006
  6. Nov 23, 2006 #5
    yes.. but it is an indeterminate form... how is it equal to zero
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