先化简,再求值6xy-3{3y的平方-(x的平方-2xy)}

[-(xy)/(x-y)^2]^4*[(x^2-xy)/x]^3*x^4/y^10÷[x/(xy-y^2)]^5=(x^4y^4)/(x-y)^8*(x-y)^3*x^4/y^10*[y^5(x-y)

1.2(Xy+Xy)-3(Xy-xy)-4Xy=2*2xy-0-4xy=4xy-4xy=02.1/2ab-5aC-(3acb)+(3aC-4aC)=1/2ab-5ac-3acb-ac=1/2ab-6a

个人觉得,不如直接计算6x-2y=-12-1=-132xy^2=2*(-2)*1/4=-1所以（6x-2y)*3/2xy^2=(-13)^3/(-1)=2197xy=-1(xy-3)(xy+1)=0(

原式=-3x³y³+6x^4y^4+4x²y³*2x²y=-3x³y³+6x^4y^4+8x^4y^4=-3x³y&su

|x-2|²+(y-3)²=0x-2=0,y-3=0x=2,y=3原式=3xy-[2x-2xy-(3x+xy)-5y]=3xy-(2x-2xy-3x-xy-5y)=3xy-2x+2

6xy-3【3y的二次方-（x的二次方-2xy）+1】=6xy-3【3y^2-x^2+2xy+1】=6xy-9y^2+3x^2-6xy-3=-9y^2+3x^2-3=-9*1^2+3*(-2)^2-3

3x平方y-2xy平方）-(xy平方-2xy平方）,=3x^2y-2xy^2-xy^2+2xy^2=3x^2y-xy^2=3*(-1)^2*2-(-1)*2^2=6+4=10

=[(xy)^2+6xy+9-(xy)^2+xy^3-9]除以(1/2xy)=(6xy+xy^3)/(1/2xy)=12+y^2代入y=-3=12+(-3)^2=21

-3（2x^2-xy）+4（x^2+xy-6)=-6x²+3xy+4x²+4xy-24=-2x²+7xy-24=-2*1/4+7*1/2*3-24=-1/2+21/2-2

先拆小括号（6x∧2-5xy-6y∧2-6x∧2+6y∧2）于是括号内等于-5xy拆开后等于-125x∧3y∧3÷2xy∧2等于-125/2x∧2y再答：把xy的值带进去代进去，结果是-5

3-2xy+3yx²+6xy-4x²y=3+4xy-x²y=3+1x2+(-1)²x2=3+2+2=7

原式=2XY+3YX^2+6XY-6X^2Y吧=8XY-3X^2Y=XY(8-3X)代入已知数：原式=-2*（8-3/2)=-13

x^2y-2（2xy^2-3x^2y-3）3xy^2,其中x,y满足|x-2|（y1=x²y-4xy²+6x²y+6-3xy²=7x²y-7xy

y/x=1/3所以x=3y原式=x(3x+y)(3x-y)/(3x+y)(3x-y)²=x/(3x-y)=3y/(3×3y-y)=3y/8y=3/8

(-3xy-7y)+[4x-3(xy+y-2x)],=-3xy-7y+4x-3xy-3y+6x=-6xy+10x-10y=-6xy+10(x-y)xy=-2,x-y=3=-6×(-2)+10×3=18

[(3x-3y)/(y平方-x平方)+(x平方-2xy+y平方)/(x平方-y平方)-(x平方-x+6)/(x+2)]/(x+y)=【-3/(x+y)+(x-y)/(x+y)-(x-3)]】/(x+y

3x^3-[x^3+(6xy-7x)+2(x^3-3xy-4y)],=3x³-x³-6xy-7x-2x³+6xy+8y=-7x+8y当x=-1,y=2时原式=7+16=2

2(xy-5xy的平方)-(3xy的平方-xy)＝2xy-10xy的平方-3xy的平方＋xy＝3xy-13xy的平方当x=-1,y=1时,原式＝-3＋13＝10

化简的结果是xy(x-2y)再问：过程？！再答：过程太麻烦了，电脑没法打。