Help with showing infinite series converges/diverges

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SUMMARY

The series defined by the function \(\frac{1}{2(\ln(n+1))^2}\) from \(n = 1\) to infinity diverges. Attempts to apply the Ratio Test and Root Test were unsuccessful, and the Integral Test leads to a non-elementary antiderivative. A comparison with the harmonic series \(\frac{1}{n}\) is suggested, as for large values of \(n\), \(\frac{1}{2(\ln(n+1))^2}\) is smaller than \(\frac{1}{n}\), indicating divergence.

PREREQUISITES
  • Understanding of series convergence and divergence
  • Familiarity with the Integral Test for convergence
  • Knowledge of comparison tests in series analysis
  • Basic calculus, including logarithmic functions
NEXT STEPS
  • Study the Integral Test for series convergence in detail
  • Learn about the Comparison Test and Limit Comparison Test
  • Explore properties of logarithmic functions in calculus
  • Review examples of divergent series, particularly harmonic series
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Students studying calculus, particularly those focusing on series convergence, mathematicians analyzing infinite series, and educators teaching advanced calculus concepts.

coreluccio
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Homework Statement



Determine whether the series converges or diverges

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

The Attempt at a Solution



Cannot find anything to compare this series to that will show it diverges. Ratio and root test both fail. Integral test requires integrating to a non-elementary anti derivative. I have no clue how to find a solution to this.
 
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You probably mean [itex]\frac{1}{2 \ln(n+1)^2}[/itex], think about comparing it with [itex]\frac{1}{n}[/itex]. Which do you think is larger for large values of n? Now can you prove it?
 

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