作业帮12x^2 xy-6y^2
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/22 03:07:40
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^-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
提出-6xy,原式=-6xy（x-2y）=-6*1*3=-18
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
题目是不是x^2y-7xy+6yx^2y-7xy+6y=y(x^2-7x+6)=y(x-1)(x-6)
（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
12x^2+xy-6y^2=(4x+3y)(3x-2y)
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-
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)
xy=1、x－2y=3则：－6x²y＋12xy²=－6xy(x－2y)=(－6)×1×3=－18
原式=-x²y+2xy²+2x²y²-4xy³-3x³+27x³y-18x²y²+2x²y-18x&