Determine whether the series is convergent or divergent

Hypnos_16
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Homework Statement



I have to find whether the following is Convergent or Divergent

∑ from n = 1 to infinity
2 / n(2n + 2)^(1/4)

Actually it's the fourth root, this is just easier to write.

Homework Equations



According to the front of the sheet it's a quiz on P-Series and Integral Test
I'm leaning more towards Integral Test.

The Attempt at a Solution



Not sure how to go about it, i think I've been looking at them for too long, i can't seem to remember how to do integrals anymore
 
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I wouldn't use the integral test.
 
Either one will work. The "P-series" test says that a series of the form \sum n^p will converge if p< 1, diverge if p\ge 1. This is not exactly of that form, but you can use the comparison test also. Can you find a p so that 1/(n(2n+2)^{1/4}&lt; n^p? The integral test says that a series \sum a_n converges if the integral \int_1^\infty a(x)dx converges where "a(x)" is just a_n with "n" replaced by "x". Can you integrate
\int_1^\infty \frac{1}{x(x+1)}dx?
 
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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