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Homework Help: Infinite series help

  1. Oct 7, 2007 #1
    [SOLVED] Infinite series help

    1. The problem statement, all variables and given/known data

    [tex]\sum- (\frac{5}{4})^n[/tex]
    i=infinity and n=0

    2. Relevant equations
    Convergence of a geometric series
    [tex]\sum (ar)^n = a/(1-r) when 0<|r|<1[/tex]

    3. The attempt at a solution
    I have to explain why this series diverges or converges. The test for divergence gives an answer of infinity so it diverges. The terms are 1, -5/4, 25/16, -125/64, 625/256... To me it looks like a geometric series with r=|-5/4| which diverges because |-5/4|[tex]\geq[/tex] 1. Is this correct?
  2. jcsd
  3. Oct 7, 2007 #2


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  4. Oct 7, 2007 #3
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