3 10x²-2 15y²分之3 2x²-2 3y²

原式=[(x+2y)/(x+y)][xy/(x+2y)]÷[(x+y)/xy]=[xy/(x+y)]×xy/(x+y)=x²y²/(x+y)²

这是反比例函数.图像是位于一、三象限的双曲线.由于x<0,因此函数图象为双曲线的第三象限部分手工绘图应用描点法.见下图

【x-y-(x-y分之4y平方)】【x+y-(x+y分之4x平方)】除以【3(x+y)-x-y分之8xy】=（x-y-x+4y)(x+y-x-4x/y)/(3x+3y-x-8x)=3y*(y-4x/y

设(x+y-z)/z=(x-y+z)/y=(-x+y+z)/x=k则（1）x+y-z=kz（2）x-y+z=ky（3）-x+y+z=kx（1）+（2）+（3）得x+y+z=k(x+y+z)∴k=1时,

1x^2y分之x^4=x²/y2ab分之ab-b^2(b不等于0）=1-b/a36abc^2分之36ab^3c=6b²/c4a^2-b^2分之（a+b)^3=（a+b）²

令(y+z)/x=(z+x)/y=(x+y)/z=ky+z=kxx+z=kyx+y=kz2(x+y+z)=k(x+y+z)2(x+y+z)=k(x+y+z)(2-k)(x+y+z)=0(x+y+z≠0

x=三分之五y代入x+y分之x-y消去y得：四分之一

解题思路：双曲线的定义解题过程：varSWOC={};SWOC.tip=false;try{SWOCX2.OpenFile("http://dayi.prcedu.com/include/readq.

1、(xy分之x²-y²)×(x-y分之x)-(y分之x)；=(x+y)(x-y)/xy×x/(x-y)-x/y=(x+y)/y-x/y=(x+y-x)/y=12、6xy²

原式=[(x+2y)/(x+y)]×[xy/(x+2y)]÷[(x+y)/xy]=[(x+2y)/(x+y)]×[xy/(x+2y)]×[xy/(x+y)]=x²y²(x+2y)/

是(x-y)分之(x+y)*(x+y)分之(x-y)如果是,那么：(x-y)分之(x+y)*(x+y)分之(x-y)=1

(x-y)/(x+y),x/(x²+xy)=1/(x+y),y/(x²-y²)=y/(x+y)(x-y)分母的最小公倍数是(x+y)(x-y)通分得：(x-y)/(x+y

x+y分之x-y=（x-y）²/(x+y)(x-y)x-y分之x+y=(x+y)²/(x+y)(x-y)

=3x/(x-4y)-(x+y)/(x-4y)-7y/(x-4y)=(3x-x-y-7y)/(x-4y)=(2x-8y)/(x-4y)=2(x-4y)/(x-4y)=2

中间是÷?再问：不是，写错了，是分解应试再问：（x²分之x²-xy）÷（y分之x-x分之y)再答：这是计算吧，怎么可能是因式分解再问：那你按计算做再答：原式=【x²分之x

解题思路：本题目应该是9y的平方吧，要不然没法做出来。解题过程：(2x-6y)/(x的平方-9y)=2(x-3y)/[(x-3y)(x+3y)]=2/(x+3y)=2/3

将（1）式通分后得到2x+2-5y+5=-10整理得到2x-5y=-17再将其乘以3,得到6x-15y=-51(3)式将（2）式乘以2,得到6x+8y=64（4）式用（4）—（3）,得到23y=115

x-4y分之3x+4y-x分之x+y-x-4y分之7y=3x/(x-4y)-(x+y)/(x-4y)-7y/(x-4y)=(3x-x-y-7y)/(x-4y)=(2x-8y)/(x-4y)=2

是这样的形式吗?[x/（x+y）+2y/（x+y）]×[xy/（x+y）]÷（1/x+1/y）一:原式=（x+2y）/（x+y）×[xy/（x+2y）]÷[（x+y）/xy]=x²y&sup