通分Y-X分之一与2X 2Y-搜答案-神马作文网

x/(xy-y²)=x/[y(x-y)]y/(x²-xy)=y/[x(x-y)]∴公分母为：xy(x-y)通分后得x/(xy-y²)=x²/[xy(x-y)]y

x-y/2x+2y=(2x^2-y+2xy)/2x=(2x^2-y+2xy)(x+y)^2/2x(x+y)^2xy/(x+y)^2=2x*xy/2x(x+y)^2

2xy/(x+y)²=2xy/((x+y)(x+y))x/(x²-y²)=x/((x+y)(x-y))所以公分母为(x+y)(x+y)(x-y)所以通分结果为：2xy/(

原式=2x2y+2xy-3x2y-3xy-4x2y=-5x2y-xy当x=-2，y=12时，原式=-9．

x²-y²=(x+y)(x-y)所以最简公分母(x+y)²(x-y)所以2xy/(x+y)²=2xy(x-y)/(x+y)²(x-y)x/(x&sup

2xy/(x+y)的平方=2xy(x-y)/(x+y)²(x-y)x/x的平方-y的平方=x(x+y)/(x+y)²(x-y)

化简得：9-12Y^2+6Y+4+12Y^2+4Y-10-10Y+X-Y+1=X-Y+4带入X、Y值得：=3

最简公分母是xy(x-y)∴2x+2y/x-y=xy(2x+2y)/xy(x-y)(x+y)²/xy=(x+y)²(x-y)/xy(x-y)再问：那么x-y/2x+2y与xy/（x

最简公分母是2(x+y)²(x-y)/2x+2y=(x-y)/2(x+y)=(x-y)(x+y)/2(x+y)²xy/(x+y)²=2×xy/2(x+y)²=2

（X+Y）2=1402X2Y*3=14400（X+Y）2=140→X+Y=70→Y=70-X①2X2Y*3=14400→XY=1200②把①代人②得：X（70-X）=1200X²-70X+1

(x-y)/(2x+2y)=(x-y)/2(x+y)=(x-y)(x+y)/2(x+y)²=(x²-y²)/2(x+y)²xy/(x+y)²=2xy/

x/(3y)的分母是3y3x/(2y²)的分母是2y²两个分式的最简公分母是6y²,通分：x/(3y)=x×2y/(3y×2y)=2xy/(6y²)3x/(2y

2x+2y=2(x+y)所以最简公分母是2(x+y)²所以(x-y)/(2x+2y)=(x+y)(x-y)/[2(x+y)²](xy)/（x+y）²=2xy/[2(x+y

第一个式子上下同乘x-y得2x平方y-2xy平方/（x+y)(x平方-y平方）第二个式子上下同乘x+y得x平方y/（x+y)(x平方-y平方）分母一样了

1/(x+y)=(x-y)/(x²-y²1/(x-y)=(x+y)/(x²-y²

1/(X-Y)与2/(X^2-Y^2)分母最小公倍数为X^2-Y^2,所以第一个分式分子分母同乘X+Y

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

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

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