已知多项式2x² 3xy-2y²-x 8y-6可分解为的形式,求mn的值-搜答案-智慧作业帮

1:已知多项式x^2+2axy-xy^2与多项式3xy-axy^2-y^3的和不含xy项所以2a=-3a=-3/2x^2+2axy-xy^2+3xy-axy^2-y^3=x^2-xy^2+1/2xy^

5x²-3xy-5y²-11xy-8x²+2y²=-3x²-3y²-14xy=-3(x²+y²)-14xy=-3x9+1

=-x-(2y-2+3x)+2(x+4)=-x-2y+2-3x+2x+8=-4x-2y+10

已知多项式-(1/5)X²Yⁿ⁺¹+XY²-3X³-6Y是六次四项式,故n+1=4,即n=3；y按降幂排列：-(1/5)x²y

(x+y)²=4x²+2xy+y²=4x²+y²-6=4x²+y²=101/2(x²+y²)-xy=1/2x1

再问：对吗?再答：对啊再答：不对我写干嘛无语再答：采纳谢谢再答：喂再答：说话啊再答：说话啊

已知x+y=3xy=2那么-x²y-xy²=-xy(x+y)=-2*3=-6如果不懂,祝学习愉快!

x+y分之xy=2,则xy/(x+y)=2xy=2x+2y(-x+3xy-y)分之(3x-5xy+3y)=(3x-5xy+3y)/(-x+3xy-y)=[3x-5(2x+2y)+3y)/[-x+3(2

解2(x+3y-2xy)-(4x+8y-2xy)=2x+6y-4xy-4x-8y+8xy=-2x-2y+4xy=-2(x+y)+4xy=-2×5+4×3=12-10=24x²-3y²

3|x+1|+2(y-1)^2=0x+1=0y-1=0x=-1y=1(x^2+4xy-2y^2)-(x^2+y)-2(y^2+xy)-1/2(x-8y^2)=x^2+4xy-2y^2-x^2-y-2y

X^2+AXY-XY^2+3XY-AXY^2-y^3=X^2+(A+3)XY-(A+1)XY^2-y^3不含XY项,所以A+3=0A=-3所以和=X^2+2XY^2-y^3

2x²+3xy-2y²-x+8y-6=2x²+3xy-2y²+A(2x-y)+B(x+2y)+AB=2x²+3xy-2y²+(2A+B)x+

-2x^2y(-1/6x^2y^2+3xy^2-xy)+xy=1/3x^4y^3-6x^2y^3+2x^3y^2+xy

-6xy-7x^(3m-1)y^2+3分之4x^3y-x^2y-5是七次多项式那么x,y的最高次项的总次数为7最高次项只能是-7x^(3m-1)y^2次数和为3m-1+2=7,∴m=3

x²-3k（1）xy-3y²+k（2）y-4x与多项式-3y²+1/3xy+4y+4x-8的和中不含xy项和y的一次项x²-3k（1）xy-3y²+k

x+y=-5,xy=63xy^2+3x^2y=3xy(y+x)=3×6×(-5)=-90

（1）-xy²+2x²y+3x³-4y³=3x³+2x²y-xy²-4y³（2）-xy²+2x²y+

1、项数=2010项,次数=2009次2、第100项：-x^1910y^99；第101项：x^1909y^100,按照y的次数写就可以了3、x=1,y=-1原式=1+1+1+……+1=2010

M=(2x^2y+xy^2)（x-2y)-(2x^2-3xy+xy^2)(-xy)很简单啊.

解2x³-3xy-y²+(x³+xy+y²)=(2x³+x³)+(xy-3xy)+(y²-y²)=3x³-2x