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Exercise 350Calculus › Single-variable calculus › SequencesL1Added 1 Nov 2026

The n-th root of n

#sequences#logarithm#growth comparison

Statement

Compute lim⁡n→∞n1/n\displaystyle\lim_{n\to\infty}n^{1/n}.

Hint

Write n1/n=e(ln⁡n)/nn^{1/n}=e^{(\ln n)/n} and use the result on the logarithm versus powers.

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Solution

Idea. The base nn grows, while the exponent 1n\frac1n shrinks. Who wins? Taking the logarithm shows that the exponent wins.

Computation. For n≥1n\ge1,
n1/n=exp⁡ ⁣(ln⁡nn).n^{1/n}=\exp\!\left(\frac{\ln n}{n}\right).
We know that ln⁡xx→0\dfrac{\ln x}x\to0 as x→+∞x\to+\infty (see the problem *The logarithm is slower than any power*), in particular along the integers. By continuity of exp⁡\exp, n1/n→e0=1n^{1/n}\to e^0=1.