-4xˇ2ˇ·(1 2xy-yˇ2)-3x·(xyˇ2-2xˇ2y)-搜答案-拍题作业网

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

对.前提是x不等于y

(4xy+12y)+(7x-(3xy+4Y-x))=4xy+12y+(7x-3xy-4y+x)=4xy+12y+7x-3xy-4y+x=(4-3)xy+(12-4)y+(7+1)x=xy+8y+8x当

(-3x^y+2xy)-(4x^+xy)=-3x^y+2xy-4x^-xy=-3x^y+xy-4x^所以填上-3x^y+xy-4x^

x²+y²-2x+4y+5=0配方：(x-1)²+(y+2)²=0所以只有x-1=0且y+2=0∴x=1,y=-2∴(X^4-y^4)/(2x^2+xy-y&#

4xy-(x+y)^2/xy(x+y)(x-y)÷x^2+xy-2y^2/x^2y+2xy^2=(4xy-x²-2xy-y²)/[xy(x+y)(x-y)]÷[(x-y)(x+2y

x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2=16x^3y^3-49x^3y^3-45^3y^3=-78x^3y^3如果本题有什么不明白可以追问,

1^2=(x^2+y^2)^2=x^4+2x^2y^2+y^4>=2x^2y^2+2x^2y^2所以x^2y^2=00

(x^-4y^)/(x^+2xy+y^)/(x+2y)/(2x^+2xy)=1.=3(a-b)/(10ab)*(25a^2b^3)/((a+b)(a-b))=15/2*(ab^2)/(a+

分子、分母都除以X^2=-7/8

（4xy+12y)+[7x-(3xy+4y-x)]=4xy+12y+7x-3xy-4y+x=xy+8x+8y=xy+8(x+y)=(-2)+8*3=-2+24=22

在线数学帮助你：这是一道关于化简求解的题目；根据题目给出的式子：X^2Y-XY^2-X+Y=56；提出XY；XY（X-Y）-（X-Y）=56；再提出（X-Y）可得；（XY-1）（X-Y）=56；因为X

x^2+4y^2=4x^2+4y^2+4xy=(x+2y)^2=4+4xy≥0,xy≥-1x^2+4y^2-4xy=(x-2y)^2=4-4xy≥0,xy≤1xy的最大最小值分别是1,-1

∵x-y=4xy，∴2x+3xy-2yx-2xy-y=2(x-y)+3xyx-y-2xy=8xy+3xy4xy-2xy=112．故答案为：112．

xˇ+yˇ+2xy=256

(x+y)²=16²→x+y=16……①x+y=-16……②(x-y)²=2²→x-y=2……③x-y=-2……④①③联立解得：x1=9,y1=7①④联立解得：

x^2+y^2-4x+6y+13=0可以化成(x-2)^2+(y-3)^2=0所以x=2,y=3后面的代数你自己算吧

4x^2y+12xy+9y

4x^2y+12xy+9y=y(4x^2+12x+9)=y(2x+3)^2

x^2y+4xy+4y

x^2y+4xy+4y=y(x²+4x+4)=y(x+2)²

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。

x^2+y^2-2x+4y+5=0(x-1)^2+(y+2)^2=0x=1,y=-2化解式子,再代入