f'(x)=(1+1/x²)lnx +(x-1/x)/x
=(1+1/x²)lnx +1-1/x²
f'(e)=1+1/e² +1-1/e²=2还少个lnx没算啊因为 lne=1f'(e)=(1+1/e²)lne +1-1/e²=1+1/e² +1-1/e²=2