2 x y 除以3-x y除以4=-1-搜答案-大师作文网

由X+Y=3XY可得X+Y-XY=2XY,用X+Y-XY替换分母中的2XY,所以(2X+2Y-XY)/(X+Y+2XY)=(2X+2Y-XY)/(2X+2Y-XY)=1

6/23

分式的计算1.3a除以4b乘以16b除以9a的平方=(3a/4b)*(16b/9a^2)=4/3a2.12xy除以5a除以8x的平方y=(12xy/5a)/8x^2y=3/10ax3.-3xy除以3x

不是.由数与字母的积组成的代数式叫做单项式,单独的一个数或一个字母也叫做单项式

解((xy+2)(xy-2)-2x^2y^2+4)除以2xy=(x²y²-4-2x²y²+4)/(2xy)=(-x²y²)/(2xy)=-x

由于xy除以x+y=2故xy=2（x+y）将这代入8x-5xy+8y除以-x+3xy-y化简得其中的（x+y）会相互约去故8x-5xy+8y除以-x+3xy-y=-2/5希望这个能帮到你over~

9x^2/2y再问：貌似是负的吧再答：没看见前面的“负”…………

已知2x-3*根号(xy)-2y=0(x>0),则x2+4xy-16y2除以2x2+xy-9y2的值是多少?2x-3*根号(xy)-2y=0(根号X-2根号Y)(2根号X+根号Y)=0根号X-2根号Y

可以先设xy=t原式=[4(t-1)^2-(t+2)(2-t)]/(1/4*t)=4(4t^2-8t+4-2t+t^2-4+2t)/t=4(5t^2-8t)/t=(20t-32)/t=20-32/t将

原式=[4(x+y)-2xy]分之[(x+y)+xy]=[4(3xy)-2xy]分之[(3xy)+xy]=10xy分之2xy=5分之1

=[(xy)^2+6xy+9-(xy)^2+xy^3-9]除以(1/2xy)=(6xy+xy^3)/(1/2xy)=12+y^2代入y=-3=12+(-3)^2=21

[4(xy-1)^2-(xy+2)(2-xy)]除以4分之1xy=[4x^2乘以y^2-8xy+4-(4-x^2y^2)]除以4分之1xy=(4x^2乘以y^2-8xy+4-4+x^2y^2)除以4分

1÷(2÷3)÷(3÷4)÷(4÷5)÷(5÷6)÷(6÷7)=1÷2×3÷3×4÷4×5÷5×6÷6×7=1÷2×7=0.5×7=3.5明白请采纳,有新问题请求助,

x²+xy-6y²=0(x+3y)(x-2y)=0∴x+3y=0或x-2y=0即x=-3y或x=2y当x=-3y时(x²-2xy+4y²)/(2x²-

x/3=y/4所以x=3y/4所以(x^2-xy)/(x^2+y^2)=(9y^2/16-3y^2/4)/(9y^2/16+y^2)=-3/25

(2x-14xy-2y)除以(x-2xy-y)=4(2x-14xy-2y)=4(x-2xy-y)2x+6xy-2y=0x-y=-3xy两边同除以xy,得1/y-1/x=-3所以1/x-1/y=3

[(xy-2)(-xy-2)-4(xy-1)^2]除以(-xy)=[-x²y²+4-4(x²y²-2xy+1)]÷(-xy)=(-x²y²+

共有5种算法：1/(2/3)/4/(5/6/7/8)/9=2.81/(2/(3/4))/(5/6/7/8)/9=2.81/(2/(3/4/5)/6/7/(8/9))=2.81/(2/(3/4/(5/6

因为x²+4y²+x²y²-6xy+1=0(x²-4xy+4y²)+(x²y²-2xy+1)=0(x-2y)²