Proving an inequality involving exponentiation

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SUMMARY

The inequality \(\left( 1 - \frac{\ln n}{kn} \right)^n > \frac{1}{n^{1/k} + 1}\) is proven to hold for all integers \(n \geq 1\) and \(k \geq 2\). The initial approach involved analyzing the limit of the quotient of the left-hand side (LHS) and right-hand side (RHS) as \(n\) approaches infinity, which simplifies to 1. A proof by induction is suggested, starting with the base case of \(n=1\) and assuming the inequality holds for an integer \(m\) to demonstrate it for \(m+1\).

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Homework Statement



Show that [tex]\left( 1 - \frac{\ln n}{kn} \right)^n > \frac{1}{n^{1/k} + 1}[/tex] holds for all integers [tex]n\geq 1[/tex] and [tex]k\geq 2[/tex].

The Attempt at a Solution



I first tried to find a proof for [tex]k=2[/tex] by showing that the quotient LHS/RHS goes to 1 and has negative slope everywhere, but this becomes rather unwieldy.
 
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I would be tempted to try a proof by induction on n. Show that the inequality holds for n=1, Assume there is an integer m for which the inequality holds and show it's true for m+1.

Mat
 

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