x²+x-1=0-x²=x-1原式=x(1-x-2)/(1-x)÷(x+1)-x(x+1)(x-1)/(x-1)²=x(x+1)/(x-1)÷(x+1)-x(x+1)/(x-1)=x/(x-1)-x(x+1)/(x-1)=(x-x²-x)/(x-1)=-x²/(x-1)=(x-1)/(x-1)=1
头疼
