[2x+3y]平方-[2x+3y][2x-y]

双十字叉乘法直接出结果（2x+y+2）（x+y+1）再问：不懂，可以说的更具体点么再答：怎么说呢，十字叉乘法有学过吗再问：一点点再答：十字叉乘法是解只含有一个未知数如x的因式分解，双十字叉乘法可以用来

x平方+3xy+2y平方/x平方y+2xy平方=（x+2y）（x+y）/x(x+2y)=(x+y)/x在我回答的右上角点击【评价】,然后就可以选择【满意,问题已经完美解决】了.

原式=x²-y²-(4x²y²+12xy²+9y²)=x²-y²-4x²y²-12xy²-

(3xy)平方/(-xy)+(x-2y)平方-(x+2y)(x-2y)=-9xy+(x-2y)(x-2y-x-2y)=-9xy+(x-2y)(-4y)=-9xy-4xy+8y²=8y

(3x平方-4y平方)+[-(x平方-2xy-y平方)]-[(3x平方-2xy-y平方)]=3x²-4y²-x²+2xy+y²-3x²+2xy+y&#

2(y-x)²-7(x-y)+6(x-y)-3(y-x)²=-(y-x)²-(x-y)=-(x-y)²-(x-y)=-(x-y)[(x-y)+1]=(y-x)(

原方程左边=（2x-y）（x+2y）=0所以x=y/2或x=-y/2将x的值分别代入到x+y/x-y得-3或-1/3

（x+y）(x+2y)=x²+xy+2xy+2y²=x²+3xy+2y²

3(x-2y)-x²y(2y-x)=3(x-2y)+x²y(x-2y)=(x-2y)(3+x²y)

y=2x/3则xy=2x2/3y2=4x2/9所以原式=(2x2/3)/(x2+4x2/9)-(4x2/9)/(x2-4x2/9)=(2/3)/(1+4/9)-(4/9)/(1-4/9)=6/13+4

因为x²+y²-4x+2y+5=0所以(x²-4x+4)+(y²+2y+1)=0所以(x-2)²+(y+1)²=o所以x=2y=-1所以下面

3(x-y)²*(y-x)²*2(x-y)=6(x-y)^(2+2+1)=6(x-y)^5再问：需要再详细一点的过程再答：3(x-y)²*(y-x)²*2(x-

(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方=x²-2xy-3y²-x²+4y²-x²+2xy-y²=(x²-

解(x-y)(x+y)-(x-2y)²+x(3x-5y)-(x-y)(x-2y)=(x²-y²)-(x²-4xy+4y²)+(3x²-5xy

x｛x-1｝-｛x＾2-y｝＝-3即x^2-x-x^2+y=-3-x+y=-3x-y=3而x＾2+y＾2-2xy=(x-y)^2=3^2=9

[(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

1.(2x-3y)^2-(y+3x)(3x-y)=4x^2-12xy+9y^2-(3x+y)(3x-y)=4x^2-12xy+9y^2-9x^2+y^2=10y^2-5x^2-12xy2.[(x-y)

（6x+2y)/(9x-3y)=6(6x/y+2)/(9x/y-3)=6,解得：x/y=5/12(3x+y)^2/(x^2-y^2)=(3x/y+1)^2/((x/y)^2-1)=(81/16)*(2

(x+2)^2-(y-3)^2=(x+y)*(x-y)x^2+4x+4-y^2+6y-9=x^2-y^24x+6y-5=0即为所求的方程

(3x-y)的平方-(2x+y)的平方-5(x-y)=(3x-y+2x+y)(3x-y-2x-y)-5(x-y)=5x(x-2y)-5(x-y)=5x^2-10xy-5x+5y