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#1 2007-02-11 17:37:45

woodoo
Member
Registered: 2007-02-10
Posts: 11

Converges or Diverges, did I do this right?

I have the problem which I must find convergent or divergent:

infinity           _____
    ∑        1/(√n^3-2)
  n= 2

I used the Comparison Test with a p-series to get that it's convergent. Is this correct?
       _____             ____
1/(√n^3-2)  <  1/(√n^3)   =  1/n^(3/2)  so it converges

Last edited by woodoo (2007-02-11 17:38:11)

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#2 2007-02-12 01:24:57

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Converges or Diverges, did I do this right?

1/√(n³-2) > 1/√n³, so that part of your reasoning doesn't work. It shouldn't be too hard to tweak it though, you're on the right lines.


Why did the vector cross the road?
It wanted to be normal.

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