如果X分之Y大于8分之3XY谁大-搜答案-拍题作业网

【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

2x+2y分之3y+x²+xy分之2xy=3y/2(x+y)+2xy/x(x+y)=3y/2(x+y)+2y/(x+y)=7y/2(x+y)如追加其它问题,再问：这道题要通分，能不能化成同分

1/X+1/Y=（X+y）/xy=1/xy=原式xy＞0x+y=1≥2根号xy即xy≤0.25则1/xy≥4则1/xy≥8-1/xy则1/X+1/Y≥8-1/xy

-12后有没有x

3x乘根号x的5次方分之y的平方-x的6次方分之y的立方=3x√（y/x^5-y/x^6）=3√（y/x-y/x^4）=3√（yx/x^4-y/x^4）=3y√（x-y）/x

=(2X/3Y)*(3X/4Y)*(4/xy)=(2x*3x*4)/(3y*4y*xy)=2x/(y^3)

x+y分之xy=2∴xy=2(x+y)-x+3xy-y分之3x-5y+8y=3(x+y)/[-(x+y)+3xy]=3(x+y)/[-(x+y)+6(x+y)]=3/5

xy/(x+y)=2∴xy=2(x+y)(3xy-x-y)/(3x-5xy+3y)=[6(x+y)-x-y]/[3x+3y-10(x+y)]=5(x+y)/[-7(x+y)]=-5/7

因为X+Y分之XY=2,所以XY=2(X+Y)代入后面的分子式得：13（X+Y)/5(X+Y)=13/5

原式=3y/2(x+y)+2xy/x(x+y)=(3xy+4xy)/2x(x+y)=7xy/2x(x+y)=7y/(2x+2y)再问：不对再答：哦，不信就算了

你传错了吧,怎么无解啊~

如果问题写清楚一些就好啦

原式(-xy/3)²*[xy(2x-y)-2x(xy-y²)]=(x²y²/9)(2x²y-xy²-2x²y+2xy²)

x^2-2xy-3y^2=0(x-3y)(x+y)=0因为x>0,y>0所以x+y>0所以只有x-3y=0x=3y(x+2y)/(x-y)=(3y+2y)/(3y-y)=5y/2y=5/2

3y/(2x+2y)+2xy/(x²+xy)=3y/(2x+2y)+2y/(x+y)=3y/(2x+2y)+4xy/(2x+2y)=7y/(2x+2y)

1/x-1/y=(y-x)/xy=3所以y-x=3xy代入后面的公式得(-5xy)/(-9xy)=5/9

3xy+3y²分之x²+xy=3y分之（x）x+3y分之2x=(x^2+6xy+9y^2)分之2x²+6xy希望能够帮到你,觉得好的话请采纳!

xy/(x+y)=2(x+y)/xy=1/21/x+1/y=1/2(3x-xy+3y)/(-x+3xy-y)=(3/y-1+3/x)/(-1/y+3-1/x)=[3(1/x+1/y)-1]/[(3-(

由（7/10）＜y/x＜（11/15）同时扩大30倍,21＜30y/x＜22.当x取1到6时,都不符合条件,当x=7时,由147＜30y＜154,y=5符合,（7/10）＜（5/7）＜（11/15）所

设x+y=axy=b,则b/a=3b=3a所以-X+3XY-Y分之2X-3XY+2Y可以写成(2a-3b)/(3b-a)=-7/8