在分式x加y分之2x中若将xy扩大到原来的两倍则所得的分式的值-搜答案-神马作文网

2/xy=2(y-x)/xy(y-x)3y/(xy-x^2)=3y^2/xy(y-x)如果不懂,请追问,祝学习愉快!

由　1/X-1/Y=5,两边同乘　XY,得出Y-X=5XY,那么　　分子　-X+XY+Y=6XY分母　2X+7XY-2Y=7XY-2(Y-X)=-3XY　　得此分式的值为－再问：还有一题x+x分之一=

x-y=x/y两边同乘以y得xy-y^2=x移项xy-x=y^2即x(y-1)=y^2x=y^2/(y-1)

(x²-2x)/(2y-xy)=x(x-2)/y(2-x)=-x/y如果不懂,请追问,祝学习愉快!

﹙x²－4y²﹚/﹙x²＋2xy＋y²﹚÷﹙x＋2y﹚/﹙2x²＋2xy﹚＝﹙x－2y﹚﹙x＋2y﹚/﹙x＋y﹚²·2x﹙x＋y﹚/﹙x＋2

x²+3分之x-2y的值为0∵x²+3>0∴x-2y=0∴x=2yx²-y²分之x²-3xy-4y²=(x-4y)(x+y)/(x+y)(x

(4-x²)/(x²y-2xy)=-(x²-4)/(x²y-2xy)=-(x+2)(x-2)/xy(x-2)=-(x+2)/xy愿对你有所帮助!

2x=-yy=-2xxy/(x^2-y^2)=x*(-2x)/[x^2-(-2x)^2]=-2x^2/[x^2+4x^2]=-2x^2/5x^2=-2/5

X-3Y分之X-Y,同因式为X+2Y.

不变啊变化后,分子变成原来的2倍(4x),分母也变成原来的2倍(2x+2y)再答：��ݷ��ʣ��Է�ʽ��ֵ��䡣再答：��ʮ��ѧ��飬רҵֵ��Ͽ��

x=-2yx²-xy分之2xy+y²=【2(-2y)y+y²】/【(-2y)²-(-2y)y】=-3y²/6y²=-0.5

1/x-1/y=2005y-x=2005xy(-x+xy+y)/(2x+6016xy-2y)=[xy+(y-x)]/6016xy-2(y-x)]=(xy+2005xy)/(6016-4010xy)=2

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

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)/

(x+3y)/(x²+xy)+(y-x)/(xy+y²)=(x+3y)[x(x+y)]-(x-y)/[y(x+y)]=[(x+3y)y-x(x-y)]/[xy(x+y)]=(xy+

x/y+y/x=(x²+y²)/xyx²+y²=(x+y)²-2xy=36-16=20原式=20/8=2.5

2(x平方-6分之7y）平方分之（x-3分之2y)平方

y-x=3xyx-y=-3xyx-2xy-y=-5xy2x+3xy-2y=2(x+y)+3xy=-6xy+3xy=-3xy分式x-2xy-y分之2x+3xy-2y=5/3

xy分之【x加y】等于2分之一xy=2(x+y)【xy加x加y】分之xy=2(x+y)/[2(x+y)+x+y]=2(x+y)/[3(x+y)]=2/3

不变.因为分子分母都同时变为原来的100倍.二十年教学经验,专业值得信赖!敬请及时采纳,在右上角点击“评价”,然后就可以选择“满意,问题已经完美解决”了.再问：.��˼