令：y=(x+e^x)^(1/x)lny=[ln(x+e^x)]/xlim(x→∞)lny=lim(x→∞)(1+e^x)/(x+e^x) //:成∞/∞型的不定式,用洛必达法则；=lim(x→∞)e^x/(1+e^x) //:又成∞/∞型的不定式,再用洛必达法则；=lim(x→∞)e^x/e^x=1得到：l...