n趋向无穷大，(1+1/n)的n次方趋近于e所以n趋向无穷大，(1+1/n)的n+m次方趋近于e^m
略去 lim(n→∞)：(1+1/n)^(n+m)=[(1+1/n)^n]·[(1+1/n)^m]=[(1+1/n)^n]·{[(1+1/n)^n]^(m/n)}=e·[e^(m/n)]=e
e^m
