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Am i doing right for these two question

  1. Apr 24, 2007 #1
    see attachment

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  2. jcsd
  3. Apr 24, 2007 #2


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    That a_n-->0 in [tex]\sum a_n[/tex] does not imply that the series is convergent. You should re-read that theorem in your notes/book more carefully to see what it's actually saying.
  4. Apr 24, 2007 #3


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    lim an= 0 is a necessary condition that
    [tex]\Sigma a_n[/tex]
    converge, not a sufficient condition!

    The first one "compares" to the sum of 1/n which does NOT converge.
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