8(x²-2x²)-x(7x y) xy-搜答案-大师作文网

先把括号化简去掉,注意去扩前的加减号,加号去括号不变号,减号去括号要变号,8（x^2-2y^2）-x（7x+y）+xy=8X^2-16y^2-7x^2-xy+xy排列一下化简后因式的顺序,8x^2-7

8（x平方-2y平方)-x(7x+y)+xy=8x平方-16y平方-7x平方-xy+xy=x平方-4y平方=(x-2y)(x+2y)手机提问的朋友在客户端右上角评价点【满意】即可.再问：太棒了！连我这

-x^y^7+y^8)(这里有问题,x的几次方?再问：就是一次方再答：(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-xy^7+y^8)(x^2+xy+y^2)=（x^8-x^7y+x^

对.前提是x不等于y

=8x²-16y²-7x²-xy+xy=x²-16y²

X²-XY+2X=O提公因数X即X（X-Y+2）=0则X=0或X-Y+2=0假如X=0那么代入X²-2XY+Y+8=0解得Y=﹣8即X=0Y=﹣8假如X≠0则X-Y+2=0即X=Y

【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

3x-2xy-8-2x+6xy-x²+6=-x²+(-2+6)xy+(3-2)x+(-8+6)=-x²+4xy+x-2-x²+2xy-y²-3x

3x²+2x²-3x-(-x+5x²)=3x²+2x²-3x+x-5x²=-2x其中x=314时,-2x=-2*314=-6285xy-8x

(x-y)^8

设X=kY.kY^2/(3k+2)Y=1/8kY^2/((2k+3)Y=1/7由上式得：3k+2=8kY,2k+3=7kY所以2/（8Y-3）=3/（7Y-2）所以Y=1/2,X=1

(5xy+4x+7y)+(6x-3xy)-(4xy-3y)=5xy+4x+7y+6x-3xy-4xy+3y=(5xy-3xy-4xy)+(4x+6x)+(7y+3y)=-2xy+10x+10y=-2x

8(x^2-2y^2)-x(7x+y)+xy=8x^2-16y^2-7x^2-xy+xy=x^2-16y^2=(x-4y)(x+4y)

原式=8x^2-16y^2-7x^2-xy+xy=x^2-16y^2=（x+4y）（x-4y）．

8（x^2-2y*2)-x(7x+y)+xy=8x²-16y²-7x²-xy+xy=x²-(4y)²=(x-2y)(x+2y)希望能帮到你,祝学习进步

（1）2x-3x-7x=-8x（2）2xy-3xy+5xy=4xy（3）5x^3y-6x-7x^3y-8x=-2x^3y-14x(4)2/3x^2-3/2xy+x^2-1/3xy+1/2xy=5/3x

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)