作业帮4y平方-(x平方 y) (x平方-4y平方)其中x等于-28 y等于18
来源：学生作业帮助网 编辑：作业帮 时间：2024/04/27 23:24:59
原式=(x²+y²+2xy)(x²+y²-2xy)/(x+y)²=(x+y)²(x-y)²/(x+y)²=(x-y)&#
(x平方-y平方)/(x+y)+(x平方-2xy+y平方)/(x-y)=(x+y)(x-y)/(x+y)+(x-y)^2/(x-y)=x-y+x-y=2(x-y)
是假命题,因为,x^2y
(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&#
x平方+y平方+2xy分之x平方-4y平方除以x平方+xy分之2y+x=(x-2y)(x+2y)/(x+y)²·x(x+y)/(x+2y)=x(x-2y)/(x+y)
4x^2-9y^2=(2x+3y)(2x-3y)
(z²-x²-y²)-4x²y²=(z²-x²-y²-2xy)(z²-x²-y²+2xy)
一式子减去二式子乘以2的差得x²-2xy-3y²=0(x+y)(x-3y)=0x=-y或x=3y当x=-y时代入一式3y²-y²=8y=±2当x=3y时代入一式
不等于再问：那应该？再问：再答：好像分解不了了………再答：楼主在？再问：在呢再答：再答：直接成这样再答：用平方差公式再问：我刚刚也做出来了再问：对呢再答：采纳下再问：再问：是这样的再答：不是呀再答：再
(x^2+y^2)^2-4x^2y^2=[(x^2+y^2)+2xy][(x^2+y^2)-2xy]=(x^2+2xy+y^2)(x^2-2xy+y^2)=(x+y)^2(x-y)^2
=x^3-y^3-(x^3+y^3)=-2y^3^3表示三次方
x^2-4y^2-x+2y=(x+2y)(x-2y)-(x-2y)=(x-2y)(x+2y-1)x^2-2x-b^2-2b=(x+b)(x-b)-2(x+b)=(x+b)(x-b-2)
(x^2+y^2)^2-4x^2y^2=(x^2+y^2+2xy)(x^2+y^2-2xy)=(x+y)^2*(x-y)^2=(x^2-y^2)^2数学佰亊嗵为你解答,希望我的回答为您带来帮助!
x平方-y平方=4（x+y）（x-y）=4（x+y）平方*（x-y）平方=4*4=16
x²-y²+5x+3y+4=（x²+4x+4）-（y²-4y+4）+x-y+4=（x+2）²-（y-2）²+x-y+4=（x+y）（x-y+
=(x²+y²)²-(2xy)²=(x²+2xy+y²)(x²-2xy+y²)=(x+y)²(x-y)
根据：a²-b²=(a+b)(a-b)(x²+y²)²-(2xy)²假设：(x²+y²)²=a²,(
(x²-y²)/(x-y)²=(x+y)(x-y)/(x-y)²=(x+y)/(x-y)
x的平方-x-4y的平方+2y=(x-2y)(x+2y)-(x-2y)=(x-2y)(x+2y-1)
x平方-4y平方-x-2y=(x+2y)(x-2y)-(x+2y)=(x+2y)(x-2y-1)