Question

1.(x/x-y)*(y²/x+y)-(x^4 y/x^4-y^4)÷(x²/x²+y²)

2.[（x/x+y）+（2y/x+y)]*(xy/x+2y)÷[(1/x)+(1/y)]
要详细过程

Answer 1

(x/x-y)*(y²/x+y)-(x^4 y/x^4-y^4)÷(x²/x²+y²)
=(xy²)/(x²-y²)-(x^4 y)/(x^4-y^4) *(x²+y²)/x²
=(xy²)/(x²-y²) - x²y/(x²-y²)
=(xy²-x²y)/(x²-y²)
=xy(x-y)/[(x+y)(x-y)]
=xy/(x+y)

[（x/x+y）+（2y/x+y)]*(xy/x+2y)÷[(1/x)+(1/y)]
=(x+2y)/(x+y) *(xy)/(x+2y) ÷[(x+y)/(xy)]
=(xy)/(x+y) *(xy)/(x+y)
=(x²y²/(x+y)²

Answer 2

1..(x/x-y)*(y²/x+y)-(x^4 y/x^4-y^4)÷(x²/x²+y²)=(xy²/x²-y² )- [x^4 y/(x²+y²)(x²-y²)* (x²+y²)/x²]
=(xy²/x²-y² )- x²y/x²-y² =xy(y-x)/(x+y)(x-y)=-xy/(x+y)