x^2 xy-6y^2 x 13y-6-搜答案-大师作文网

因为x/y=2所以x=2y是[x^2-xy+3y^2]/[x^2+xy+6y^2]吧=(4y^2-2y^2+3y^2)/(4y^2+2y^2+6y^2)=5y^2/12y^2=5/12

x^2-xy-6y^2+3xy+y+2

3xy是3x原式=(x-3y)(x+2y)+3x+y+2十字相乘x-3y2×x+2y1所以原式=(x-3y+2)(x+2y+1)

对.前提是x不等于y

-2x^+xy+y^-6x-y-2

-2x^+xy+y^-5x-y-2=-[2x^-xy-y^+5x+y+2]=-[(2x+y)(x-y)+5x+y+2]=-[(2x+y)(x-y)+2*(2x+y)+(x-y+2)]=-[(2x+y)

(x+y-2xy)(x+y-2)+(1-xy)^2=(x+y)^2-2(1+xy)(x+y)+4xy+1-2xy+x^2y^2=(x+y)^2-2(1+xy)(x+y)+(1+xy)^2=(x+y)^

x^+2xy+y^+4=16(x+y)²=16-4=12(1)x^-2xy+y^=16(x-y)²=16(2)(1)-(2)2y*2x=-4xy=-1(3xy+6y^)+|x^-(

=xy(x-y)×[-xy/(x-y)]=-(xy)²=-x²y²

x=-1,y=-6或x=6,y=1代入式子得x^2-xy^2=37或30x^2y+xy^2=-42或42

因式分解 2x^+xy-6y^

题目不清楚啊,那个是几次方啊?算了,我就按2次方做了啊2x^2+xy-6y^2=(2x-3y)(x+2y)6（x+y)^2-5(x+y)-1=[6(x+y)+1][(x+y)-1]=(6x+6y+1)

【x²+xy/（x-y）】/【xy/（x-y）】=【x²（x-y）/（x-y）+xy/（x-y）】/【xy/（x-y）】={【x²（x-y）+xy】/（x-y）}/【xy

x^2-7xy+6y 因式分解

题目是不是x^2y-7xy+6yx^2y-7xy+6y=y(x^2-7x+6)=y(x-1)(x-6)

急不解决问题最后还是靠自己多动脑看课本其实都是课本上的再问：你看看啊！课本上没有，不会才问的！.........

xy/x+y=6∴xy=6(x+y)3x-2xy+3y/-x+3xy-y=[3x-12(x+y)+3y]/[-x+18(x+y)-y]=-9(x+y)/17(x+y)=-9/17再问：你在啊？再答：在

[(x-y)/(x+3y)]/[(x^2-y^2)/(x^2+6xy+9y^2)]-xy/(x+y)=(x-y)/(x+3y)*(x+3y)^2/(x-y)(x+y)-xy/(x+y)=(x+3y)/

X²-XY-6Y²+2X-Y+1=(X+1)²-Y(X+1)-6Y²=(X+1-3Y)(X+1+2Y)再问：学生不才老师您第一步我就不知道怎么得到的再答：X2-

6x^2y^2+xy-15

6x²y²+xy-15=(2xy-3)(3xy+5)

1、(-7x^y)(2x^y-3xy^3+xy)=-14x^(2y)+21x^(y+1)y^3-7x^(y+1)y;2、((x-y)^6)/((y-x)^3)/(x-y)=-(x-y)^3/(x-y)

已知x+xy=-2,xy-y=-6则X+Y=42x｛-4y-3[（x+xy）²+x]-½[（y-xy）²-2y]=2x｛-4y-3[（-2）²+x]-&fr

不会

原式=-x²y+2xy²+2x²y²-4xy³-3x³+27x³y-18x²y²+2x²y-18x&