(x-x^2)/（-x^2-3x-2）-(x^2+1)/(x^2+3x+2)=(x²-x)/(x²+3x+2)-(x²+1)/(x²+3x+2)=(x²-x-x²-1)/(x+1)(x+2)=-(x+1)/(x+1)(x+2)=-1/(x+2)