$\lim_{n \to \infty} n\ln\left(1+\frac{1}{n}\right)$ using L'Hòpital rule show that this is $1$. Can you do this since there isn't a division and $n$ will obviously tend to infinity and $\ln\left(1+\frac{1}{n}\right)$ will tend to $0$? So there limits aren't matching?
So I set $u=n $
$du=1$
$v= \ln\left(1+\frac{1}{n}\right)$
$dv= -\frac{1}{n^2+n}$
Hence $\ln\left(1+\frac{1}{n}\right) - \frac{1}{n+1}$ in which both of these tend to $0$ so I am complete lost.
Hint
$$\lim_{n\to \infty} n\ln \left(1+\frac1n\right)=\lim_{n\to \infty} \frac{\ln \left(1+\frac1n\right)}{\frac 1n}.$$