h→0lim [ln(x+h)-ln(x)] / h=lim (1/h)*ln(1+(h/x))=lim (1/x)*(x/h)*ln(1+(h/x))=(1/x)*lim (x/h)*ln(1+(h/x))=(1/x)*ln(lim (1+(h/x))^(x/h))由重要的极限：lim(h→0) (1+h)^(1/h)=e=(1/x)*lne=1/x其实这个极限就...