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Using a fact to find a limit?

  1. Dec 15, 2008 #1
    Using a fact to find a limit??

    If I were given a problem to find this limit:


    using the fact that


    how would I do it?

    I know how to evaluate this limit using L'Hopital's Rule...but I am not to sure on evaluating using this "fact."
  2. jcsd
  3. Dec 15, 2008 #2
    Re: Using a fact to find a limit??

    Well, since x is not a variable in [tex]\left(\frac{n+4}{n-4}\right)^n[/tex], we have:

    [tex]\lim_{x\rightarrow \infty} \left(\frac{n+4}{n-4}\right)^n = \left(\frac{n+4}{n-4}\right)^n[/tex].

    Assuming you meant [tex]\lim_{n\rightarrow\infty}[/tex], start by substituting 1/x for n in the function, and take the limit of the result as [tex]x\rightarrow0^+[/tex].

    P.S. this belongs in homework help.
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