(X^2-4X+4)/(X^2+X)÷[3/(X+1) -X+1] + 1/(X+2)=(x-2)²/[x(x+1)] ÷[(3-x²+1)/(x+1)] + 1/(X+2)=(x-2)²/[x(x+1)] *(x+1)/[-(x+2)(x-2)] + 1/(X+2)=(x-2)/[-x(x+2)] + 1/(x+2)=(-x+2+x)/[x(x+2)]=2/(x²+2x)若x为方程x²+2x-1=0的解,那么:x²+2x=1所以:所求式子=2/(x²+2x)=2/1=2