xy根号x2+y2

(x2+xy+y2)-4xy(x2+y2)想疯了!乱做后得出2(x+y)(1-4xy)+xy只要2分,不必理睬

因式分解x2+4xy-4y2x2-2（根号2）x-3x2+4xy-4y2=(x^2+4xy+4y^2)-8y^2=(x+2y)^2-8y^2=(x+2y+2√2y)(x+2y-2√2y)x2-2（根号2）x-3=x^2-2√2x+2-5=(

已知xy满足x2+y2-6x+2y+10=0,求立方根号x2-y2的值条件变换：(x-3)^2+(y+1)^2=0即：y+1=0x-3=0所以：立方根号x2-y2=2x2+y2-6x+2y+10=0(x-3)^2+(y+1)^2=0=>x=

(x2+2xy+y2)(x2-xy+y2)2化简(x^2+2xy+y^2)(x^2-xy+y^2)^2=(x+y)^2*(x^2-xy+y^2)^2=((x+y)(x^2-xy+y^2))^2=(x^3+y^3)^2=x^6+2x^3y^3

(x2-2xy+y2)-(x2+2xy+y2)=什么-4xy-4xy(x2-2xy+y2)-(x2+2xy+y2)=x2-2xy+y2-x2-2xy-y2)=-4xy(X-y)2-(x+y)2=(x-y-x-y)(x-y+x+y)=-2y.

(x2+xy+y2)(x2+xy+2y2)-12y4=(x²+xy+y²)(x²+xy+y²+y²)-12y的4次方=(x²+xy+y²)²+y²(x

(x2+xy+y2)-4xy(x2+y2)因式分解2z=2x^22xy2Y^2-2x-2y=(x^22xyy^2)(x^2-2x)(y^2-2y)2z2=(x^22xyy^2)(x^2-2x1)(y^2-2y1)=(xy)^2(x-1)^2

y=根号x-3+根号3-x+5求x2-xy+y2的值由题意可得：x-3=3-x=0解得：x=3那么：y=0+0+5=5所以：x²-xy+y²=9-15+25=19

因式分解x2+xy-3y2x²+xy-3y²=x²+xy+y²/4-13y²/4=(x+y/2)²-13y²/4=(x+y/2+√13y/2)(x+y/2-√13/2)

(x-y)(x2+xy+y2)x^3+x^2y+xy^2-x^2y-xy^2-y^3=x^3-y^3就是x的三次方减去y的三次方：x^3-y^3

(x+y)(x2-xy+y2)原式=(x+y)[(x-y)²+xy]=(x²-y²)(x-y)+x²y+xy²=x³-x²y-xy²+y³+x

X2+3xy+y2因式分解=[x+(3-√5)/2*y][x-(3-√5)/2*y]有点牵强,但这是唯一的答案了无解的吧x^2+3xy+y^2=x^2+2xy+y^2+xy=(x^2+2xy+y^2)+xy=(x+y)^2+xy(x+y)2

x2-2xy+y2-9是分解因式吧!x2-2xy+y2-9=(x-y)^2-3^2=(x-y-3)(x-y+3)

解关于x,y的方程组{x2-y2+根号(x2+y2)=axy=0解关于x,y的方程组{x2-y2+根号(x2+y2)=axy=0由xy=0,得x=0,或y=0当x=0时,代入方程1：-y^2+根号y^2=a,即y^2-|y|+a=0,解得|

已知2x-3*根号(xy)-2y=0(x>0),则x2+4xy-16y2除以2x2+xy-9y2的值是多少?正确答案是二十七分之十六.已知2x-3*根号(xy)-2y=0(x>0),则x2+4xy-16y2除以2x2+xy-9y2的值是多少

已知x2分之(根号5)-1y=2分之(根号5+1)求（1）2x2-xy+2y2（2）x2-y2-xy已知x=2分之(根号5-1)y=2分之(根号5+1)x+y=根号5,x-y=-1,xy=1（1）2x^2-xy+2y^2=2(x^2+y^2

计算：(xy-x2)÷xy分之x2-2xy+y2(xy-x2)÷xy分之x2-2xy+y2=(xy-x²)÷(x-y)²/xy=x(y-x)*xy/(y-x)²=x²y/(y-x)³

-（x2-2xy-y2)+(5x2-2xy-3y2)-（x2-2xy-y2)+(5x2-2xy-3y2)化简-(x²-2xy-y²)+(5x²-2xy-3y²)=-x²+2xy+y²

已知x2-3xy-4y2的绝对值+2倍根号x2+4xy+4y2-1=0求3x+6y的值x²-3xy-4y²=0x²+4xy+4y²-1=0由(1)得(x-4y)(x+y)=0x=4yx=-y由(2)得

已知两个实数xy,满足x2+y2=1,求x+根号3y最大值设x+√3y=t,那么直线x+√3y-t=0与圆x^2+y^2=1有公共点所以圆心O到直线的距离小于等于半径即|t|/2≤1∴|t|≤2解得-2≤t≤2即x+√3y的最大值为2