5（x-y)'3+10(y-x)'2;16a'4-72a'2b'2+81b'4;4a'2b'2-(a'2+b'2)'2;18b(a-b)'2-12(a-b)'2牛头不对马嘴。

5x^3y(x-y)^3-10x^4y^3(y-x)^2因式分解 5x^3y(x-y)^3-10x^4y^3(y-x)^2 (x+5y)^+(2x+10y)(3x-y)+(3x-y)^ (x+5y)²-(2x+10y)(3x-y)+(3x-y)² 5X^3Y(X-Y)-10X^4Y^3(Y-X)^2因式分解 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) x-y/7 - x+y/10 =1/2 2(x-y)-5(x+y)=3修改、、、、（x-y)/7-(x+y)/10=1/2 2(x-y)-5(x+y)=3 { x-y/7-x+y/10=1/2 {2(x-y)+5(x+y)=3 { x-y/7-x+y/10=1/2 {2(x-y)+5(x+y)=3 10/x+y+3/x-y=-5 15/x+y-2/x-y=-1（用换元法解此方程组） 解分式方程：10/(x+y)+3/(x-y)=-5,15/(x+y)-2/(x-y)=-1 3/(X-Y)+10/(X+Y)=-5 2/(X-Y)-15/(X+Y)=1 解分式方程组 {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 因式分解1.(x^2-y+1)(x^2+1)+x^2y+y-x^2 2.(x+5y)^2+(2x+10y)(3x-y)+(y-3x)^2 （1）x(x+10)-2(3x-2) 分解因式y(2y+1)-y(y-1)+1 2x(2x-y)+y(y-2x) 2y(y-2)-y(y-4)-1 x(x+8)-8(x+2) (a+2)(a-2)-5 （x-3)(a-2)-5 (x+3)(x+4)+4分之1 化简:5(x-y)+2(x+y)-3(x-y) 绝对值化简|x-y+1|-2|y-x-3|+|y-x|+5y