1.Y^2-9(x+y)^2

1.Y^2-9(x+y)^2 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 9(x-y)-12(y-x)^2 (x+y)^2+6(x+y)+9 (x+y)^2-9(x+y)+18 化简y(x+y)+(x+y)(x-y)-x^2 计算：1.（x-1)^2+2(1-x) 2.(x-y)/(x+3y)÷(x^2-y^2)/(x^2+6xy+9y^2)-2y/(x+y）1.（x-1)^2+2(1-x)2.(x-y)/(x+3y)÷(x^2-y^2)/(x^2+6xy+9y^2)-2y/(x+y） 1.(16y^4-9x^4)/(-3x^2-4y^2) 2.(-2x+y)(-2x-y) 【2(x-y)(x-y)(x-y)-8(x-y)(x-y)(x+y)+6y(x-y)(x-y)]/2(x-y)(x-y) (x+y)(x-y)-(x-y)^2如题 (x+y)(x-y)-(x-y)^2 [(x-y)^2-(x+2y)(x-2y)]/y 1.（x+2)^2-(x+y)^32.(x-y)^2-(x-y)^33.(x-y)^2-(y-x)^3 (x-2y)^2-6(2y-x)(x+y)+9(x+y)^2因式分解 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 81/8*(-x-y)^6*(x-y)^3*4/9(x+y)^4*(y-x)^2 计算(x-y)^7÷(y-x)^6+9-x-y)^3÷(x+y)^2 3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 9(x+y)-2(x+y)-6(x+y)+18(x+y)合并同类项