Determining Divergence or Convergence in Series

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badirishluck
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Homework Statement


[tex]\sum[/tex] (2n[tex]^{2}[/tex]+3n)[tex]/\sqrt{5+n^{5}}[/tex]
index n=1 to infinity

Homework Equations





The Attempt at a Solution


I tried both the Ratio Test (limit as n goes to infinity of a[tex]_{n+1}[/tex][tex]/a_{n}[/tex]) and the Limit comparison test (limit as n goes to infinity of [tex]a_{n}[/tex]/ [tex]b_{n}[/tex]) but wasn't able to come up with the same answer from the two tests. What am I doing wrong?
Does it converge or diverge? How?
 
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try breaking it into 2 pieces and see what you can do with the individual pieces, see if
[tex]\sum[/tex] (2n[tex]^{2}[/tex])[tex]/\sqrt{5+n^{5}}[/tex]
converges, if it does then the whole thing does since the 2nd term is smaller, if it doesn't then the whole thing does not converge.