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Infinite series

  1. Sep 23, 2004 #1
    Would someone plz help me w/ the problems below? Thanks so much
    Determine whether the sequence converges or diverges, n, if it converges, find lim as n approaches infinity of "an" (subscript "n")
    1) an= e^(n) sin(n)
    2) an = e^(2n)/ [4^n]
  2. jcsd
  3. Sep 23, 2004 #2


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    What determines whether a series converges, or not ?

    (what tests are there to check for convergence ?)
  4. Sep 23, 2004 #3
    more like finding a derivative of those
  5. Sep 23, 2004 #4
    I'm not sure if you titled this thread right; this is a sequence question but that's ok.

    One way to get a handle on convergence is to plug in a few values for n and see if there is a pattern in the higher n (as n approaches infinity). Try this for 1) and see what happens. I think it diverges.

    For 2) you can do the same thing and/or rewrite it first into
    then you should have a theorem which states that since E/4>1, the sequence diverges.
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