Proving That The Series is Convergent or Divergent

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SUMMARY

The series \(\sum ( \frac{1}{3} )^{\ln(n)}\) converges, as demonstrated through the transformation of the term into \(n^{\ln(3)}\). The simplification process involves recognizing that \(3^{\ln(n)}\) can be expressed as \(n^{\ln(3)}\), allowing for a clearer analysis of convergence. The key insight is using the properties of logarithms and exponentials to rewrite the series in a more manageable form.

PREREQUISITES
  • Understanding of series convergence and divergence
  • Familiarity with logarithmic and exponential functions
  • Knowledge of calculus, specifically topics covered in Calculus II
  • Ability to manipulate mathematical expressions involving logarithms
NEXT STEPS
  • Study the Ratio Test for series convergence
  • Learn about the Root Test and its application in determining convergence
  • Explore the properties of logarithms and exponentials in depth
  • Practice problems involving series transformations and convergence criteria
USEFUL FOR

Students in calculus courses, particularly those preparing for exams in series convergence, and anyone looking to strengthen their understanding of logarithmic transformations in mathematical series.

jsewell94
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Homework Statement



Determine whether the following series converges or diverges:
\sum_{}^{} ( \frac{1}{3} )^{ln(n)}

Homework Equations



N/A

The Attempt at a Solution



See attached document..

I had my Calc 2 final today, and this was our hard problem...but I don't know if my method is valid or not. Could you help me determine if it is? And if it's not, could you tell me where the flaw in my reasoning is/a better method?
 

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jsewell94 said:

Homework Statement



Determine whether the following series converges or diverges:
\sum_{}^{} ( \frac{1}{3} )^{ln(n)}

Homework Equations



N/A

The Attempt at a Solution



See attached document..

I had my Calc 2 final today, and this was our hard problem...but I don't know if my method is valid or not. Could you help me determine if it is? And if it's not, could you tell me where the flaw in my reasoning is/a better method?

It looks ok to me. You could shorten the whole argument up a lot. 3^{ln(n)}=(e^{ln(3)})^{ln(n)}=e^{ln(3) ln(n)}=(e^{ln(n)})^{ln(3)}=n^{ln(3)}. Just use ln(3) for k.
 
Dick said:
It looks ok to me. You could shorten the whole argument up a lot. 3^{ln(n)}=(e^{ln(3)})^{ln(n)}=e^{ln(3) ln(n)}=(e^{ln(n)})^{ln(3)}=n^{ln(3)}. Just use ln(3) for k.

Oh wow, that makes sense!

Yeah, I just..couldn't figure out the easy way in the 15 minutes I had left on the test :(
Yay! That means I was the only one who got it :D
 

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