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Homework Help: Strange infinite series problem using integral test.

  1. Apr 14, 2008 #1
    1. The problem statement, all variables and given/known data
    I need to show that

    [tex]\Sigma\frac{1}{nlnnlnlnn}[/tex]

    from n=27 to n=10^(100,000)

    is approximately equal to 8.1
     
  2. jcsd
  3. Apr 14, 2008 #2
    i did the u substitution, u =nlnn

    and i get

    [tex]\int\frac{1du}{u}[/tex]

    which just becomes [lnu]
    which becomes: [ln(lnlnn)] evaluated from 27 to 10^100,000
     
  4. Apr 14, 2008 #3

    exk

    User Avatar

    is the denominator of your summation n*ln(n)*ln(ln(n))?
     
  5. Apr 15, 2008 #4
    yea it is
     
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