x(y-x)÷x^2-2xy+y^2\xy·x-y\x^2数学高手来题目更改下，数学题目：先化简再求值： 4-x/x-2÷(x+2-12/x-2),其中x=根号3-4 好的悬赏10000000000000000000000000000大洋

计算：(x+y/x-y)÷(xy+x^2) (x^2-xy)y÷y-x/xy怎么做? (-x-y)(x^2+xy+y^2) 化简x^-y^/x^-2xy+y^ 2*(x-y)²(y-x)(xy) （x^2+xy/x-y)/（xy/x-y)计算 (xy-x²)÷(x²-2xy+y²/xy)×（x-y/x²） x-y/x²÷x²-2xy+y²/xy*（xy-x²） 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) (x+y)/x /(x-(2xy-y^2)/x) 因式分解 x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² X-Y/2X+2Y XY/X+Y² 因式分解：x×x-xy-2y×y-x-y （x-y/x+y）^2÷（y-x/x^2+2xy+y^2)^2 代数 x^-y^/ x^-(y-z)^ 除以 x^+2xy+y^/(x-y)^-z^ 乘 x^+xy-xz/x^-xy 谁帮我化简：[(x+y)(x-y)-(x+y)^2-2y(x-y)-2xy]÷xy 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) (x-y)[(x+y)^2-xy]+(x-y)[(x-y)^2+xy]