令t=1/n趋于零
lim=lim(e^(ln(1+t)/t)-e)/t
=e lim(e^(ln(1+t)/t-1)-1)/t
等价代换
=e lim(ln(1+t)/t-1)/t
=e lim(ln(1+t)-t)/t²
洛必达法则
=e lim(1/(1+t)-1)/2t
=e lim-t/2t(1+t)
=-e/2
lim(n->∞) n[(1+1/n)^n-e]
=lim(n->∞) n{e^[n*ln(1+1/n)]-e}
=lim(n->∞) en{e^[n*ln(1+1/n)-1]-1}
=e*lim(n->∞) n*[n*ln(1+1/n)-1]
=e*lim(n->∞) n^2*[ln(1+1/n)-1/n]
=e*lim(n->∞) [ln(1+n)-lnn-1/n]/(1/n^2)
=e*lim(n->∞) [1/(1+n)-1/n+1/n^2]/(-2/n^3)
=(-e/2)*lim(n->∞) n/(n+1)
=-e/2