Convergence Test for 1/(sqrt(k+5)) - How to Determine Series Convergence?

raincheck
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Homework Statement


Determine whether the series converges:
1/(sqrt(k+5))


Homework Equations


well i think I'm supposed to use the integral test, which has you take the integral of the series and the limit too..


The Attempt at a Solution


.. I'm just not sure how to begin, for some reason I'm completely BLANKING on how to take limits.. i know that the series diverges, but i don't know how to actually get that answer.
 
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There is also that for all k, \frac{1}{\sqrt(k+5)}>\frac{1}{k+5} and \sum \frac{1}{k+5} is essentially the harmonic series. :rolleyes:

But I don't understand why you say you don't know where to begin while just before you were suggesting the use of the integral test.. :confused:
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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