Am i doing this right?/convergence of sequences

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SUMMARY

The limit of the sequence defined by a_n=(\frac{1}{n})^{\frac{1}{\ln{n}}} converges to e^{-1} as n approaches infinity. The solution involves taking the natural logarithm of the sequence, simplifying it to \ln{y}=-1, and then exponentiating to find the limit. The approach is confirmed to be correct, aligning with the answer provided in the textbook. The discussion clarifies that the problem presents a constant sequence in a non-obvious format.

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Homework Statement


[tex]a_n=(\frac{1}{n})^{\frac{1}{\ln{n}}}[/tex]


Homework Equations





The Attempt at a Solution



[tex]\lim_{x\rightarrow \infty}(\frac{1}{n})^{\frac{1}{\ln{n}}}[/tex]
[tex]y=(\frac{1}{n})^{\frac{1}{\ln{n}}}[/tex]
[tex]\ln{y}=\frac{\ln{\frac{1}{n}}}{\ln{n}}[/tex]
[tex]\ln{y}=\frac{\ln{1}-\ln{n}}{\ln{n}}[/tex]
[tex]\ln{y}=\frac{\ln{1}}{\ln{n}}-\frac{\ln{n}}{\ln{n}}[/tex]
[tex]\ln{y}=0-1[/tex]
[tex]e^{\ln{y}}=e^{-1}[/tex]
[tex]\lim_{x\rightarrow \infty}(\frac{1}{n})^{\frac{1}{\ln{n}}}=e^{-1}[/tex]

the back of my book says the answer is indeed [itex]e^{-1}[/itex] but I am not sure if this is the way to go to for the solution or whether I am supposed to rewrite it as something similar to [itex]\lim_{x\rightarrow \infty}(1+\frac{x}{n})^{n}[/itex]
 
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You steps are fine. That problem gives a constant sequence, just written in a non-obvious way.
 

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