化简:X减去2Y分之X减去Y除以x的平方减去-搜答案-智慧作业帮

x+3y分之2x-y等于2(2x-y)/(x+3y)=2代数式x+3y分之4x-2y减去2x-y分之4x+12y=2(2x-y)/(x+3y)-4(x+3y)/(2x-y)=2*2-4*(1/2)=4

(2x-y)/(x+3y)=2所以原式=2(2x-y)/(x+3y)-3(x+4y)/(2x-y)=2(2x-y)/(x+3y)-3/[(2x-y)/(x+3y)]=2×2-3/2=5/2

x/(y-x)

1/x-1/y=2y-x=2xyx-y=-2xy(3x+7xy-3y)/(2x-3xy-2y)=[3(x-y)+7xy]/[2(x-y)-3xy]=[-6xy+7xy]/[-4xy-3xy]=xy/[

等于0说明x加1绝对值和y减2平方都等于0.于是x＝－1.y＝2.最后式子为－3的－3次方.就是－3的3次方分之一.等于－27分之一

x²+y²-2x-4y+5=0,可化为(x²-2x+1)+(y²-4y+4)=0,即(x-1)²+(y-2)²=0,因此x-1=0,y-2=

1.33又五分之一2.213.13分之124.a=_-3___时,它有最大值为_3___

x分之1-y分之1=4(xy)分之(y-x)=4y-x=4xyx-y=-4xy(x-2xy-y)分之(2x+xy-2y)=[(x-y)-2xy]分之[2(x-y)+xy]=(-4xy-2xy)分之(-

1/X-1/Y=4Y-X=4XY(2X+XY-2Y)/(X-2XY-Y)=[2(X-Y)+XY]/[(X-Y)-2XY]=7/6

4（x+y)-3(x-y)=14x+7y=14(x+y)/2+(x-y)/3=6两边同乘以6,得3(x+y)+2(x-y)=365x+y=36则x+7(36-5x)=14x=7,y=1

得xy分之y-x=3得y-x=3xy带入得-9xy-5xy分之-3xy-2xy得14分之5..求采纳.谢谢

y=(5x-1)/(4x-2)=5/4(x-1/5)/(x-1/4)=5/4(x-1/4+1/20)/(x-1/4)=5/4（1+1/20)/(x-1/4)=5/4+(1/16)/(x-1/4)定义域

根号下大于等于0x²-4>=0,x²>=44-x²>=0,x²

3的2x-1次方减去27分之1>=03的2x-1次方>=27分之1=3的负三次方所以2x-1>=-32x>=-2x>=-1

如果问题是：1／2（x的平方＋y的平方）－xy=2

2/(x-y)-(x+y)/(x-y)^2=[(2x-2y)-(x+y)]/(x-y)^2=(x-3y)/(x-y)^2

(x^2-4y^)\(x+y)^2乘以2x(x+y)/(x+2y)=2x(x-2y)\(x+y)

解1题原式=[(x+y)/x]-[x/(x-y)]+[y²/(x²-xy)]=[(x+y)/x]-[x/(x-y)]+{y²/[x(x-y)]}={(x+y)(x-y)/

大哥那个平方是整体的平方还是那6x-4y分之1-8y的平方,题目说清楚点