n→∞时
lim e^(1/n) * 1/n +e^(2/n)* 1/n+...+e^(n/n)* 1/n
=lim (e^(1/n) + (e^(1/n))^2+...+(e^(1/n))^n)/n
=(分子等比数列求和) lim (e^(1/n)(1-(e^(1/n))^n))/(n(1-e^(1/n)))
=(分母1-e^(1/n)与-1/n等价) lim (e^(1/n)(1-e)/(n(-1/n))
=e-1
n→∞时
lim e^(1/n) * 1/n +e^(2/n)* 1/n+...+e^(n/n)* 1/n
=lim (e^(1/n) + (e^(1/n))^2+...+(e^(1/n))^n)/n
=(分子等比数列求和) lim (e^(1/n)(1-(e^(1/n))^n))/(n(1-e^(1/n)))
=(分母1-e^(1/n)与-1/n等价) lim (e^(1/n)(1-e)/(n(-1/n))
=e-1