(x->+∞)lim[(x+2)ln(x+2)-2(x+1)ln(x+1)+xln(x)]*x=(x->+∞)[(x+2)ln(x+2)-2(x+1)ln(x+1)+xln(x)]/(1/x),【为0/0型】用罗比达法则=(x->+∞)-[ln(x+2)+1-2ln(x+1)-2+ln(x)+1]/(1/x^2),=(x->+∞)lim-[ln(x+2)-2ln(x+1...