题目

xy²/(x²y) - y×x²/(x²+x)=
(x²-3x)/(x²-5x×2x) - 10/(x²-6x+9)=
2a/(a²-4) - 1/(a-2)=
2/(1-a ) - 1/(a-1)=
x²-1/(x²-x-2)除以x/2x-4,其中x=1/2
[x-x/(x+1)]除以[x/(2x-4)] ,其中x=√2+1

提问时间：2021-12-21

答案

xy²/(x²y) - y×x²/(x²+x)=y/x-x²y/x(x+1)=y/x-xy/x+1=((x+1)y-x²y)/x(x+1)=(xy+y-x²y)/x(x+1)(x²-3x)/(x²-5x×2x) - 10/(x²-6x+9)=x(x-3)/(-9x²)...