Convergence or Divergence of a Series with Sinusoidal General Term

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Homework Statement



an = sum of n * sin(\frac{1}{n} )from n =1 to n =infinity

Homework Equations



Test the series for convergence or divergence

The Attempt at a Solution


I tried the comparison test with bn = sum of n but it fails because an < bn
which means a series smaller than a divergent series and this gives me no information about the an ... I tried also the integral test but I couldn't do the integration ... so what do u think guys ?
 
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Try the Nth Term Test. :smile:

Hint: Without doing the test, you can see that you'd be adding 1 forever...
 
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check the problem again
 
It's not nice to change the question when the expert isn't looking...

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Hence by Cauchy's Fundamental test for Divergence, as the limit is not zero, the series diverges. (http://www.math.oregonstate.edu/hom...StudyGuides/SandS/SeriesTests/divergence.html)
 
Since this isn't an alternating series, does the general term go to zero as n goes to infinity?

Edit: Didn't see SVXX's post before I replied. :wink:
 
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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