4x-3y/x-2y÷6y-8x/y-2x

1.（（y+2x)(-2x+y)+4(x+2y)^2)/3y 2.（2(x-y)^3-8(x-y）^2(x+y)+6y( x^8-x^7y+x^6y^2-x^5y^3+x^4y^4-x^3y^5+x^2y^-xy^7+y^8 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= 计算：(x-y)^7÷(y-x)^6+(-x-y)^3÷(x+y)^2 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) (x+3y-4)(2x-y) x/x-y*y^2/x+y-x^3y2/x^4-y^4/x^2/x^2+y^2