x减x分之2xy减y的平方-搜答案-神马作文网

原式=-y(x-2)分之x(x-2)=-y分之x

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

通分为分母是（x+y)⒉(x-y),即为2xy（x-y）/（x+y)⒉(x-y)和x（x+y）/（x+y)⒉(x-y)

（x的平方-y的平方)分之2xy+(x+y)分之x-(y-x)分之y=（x的平方-y的平方)分之2xy+(x+y)分之x+(x-y)分之y=(x²-y²)分之[2xy+x(x-y)

x减1分之x平方减1,化简为x+1得2005+1=2006第二问不太清楚

（x分之x-y）-（y分之x+y）+（2xy分之x的平方-y的平方）=1-y/x-1-x/y+(x^2-y^2)/2xy=-2(y^2+x^2)/2xy+(x^2-y^2)/2xy=-(x^2+3y^

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

x-3y=0x=3y原式=(2x+y)(x-y)/(x-y)²=(2x+y)/(x-y)=(6y+y)/(3y-y)=7y/2y=7/2

x/y=2所以x=2y所以xy=2y²x²=4y²(x²-xy+3y²)/(x²+xy+6y²)=(4y²-2y&sup

x(x-1)-(x^2-y)=-2x^2-x-x^2+y=-2x=y+2(x/2)^2+y^2-xy=((y+2)^2/4)+y^2-(y+2)y=y^2-4y+4

如果题目是:"x的平方减xy分之y加y的平方减xy分之x",那么就是你的那个答案.y/(x^2-xy)+x/(y^2-xy)=y/[x(x-y)]+x/[y(y-x)]=y^2/[xy(x-y)]-x

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)

3∵x/y=1/2∴y=2x故（x^2+2xy+y^2)/(x^2-xy+y^2)=(x+y)^2/(x^2-xy+y^2)=(x+2x)^2/(x^2-x·2x+4x^2)=9x^2/(3x^2)=

X减Y减1分之X的平方减2XY加Y的平方减1=(x^2-2xy+y^2-1)/(x-y-1)=((x-y)^2-1)/(x-y-1)=(x-y+1)(x-y-1)/(x-y-1)=x-y+1

x²-7xy+12y²=(x-4y)(x-3y)=0x=4y或x=3yx=4y时(x²-xy+y²)/2xy=(16-4+1)y²/8y²=

2y-xy分之x的平方-2x=x（x-2）/y(2-x)=-x/y;很高兴为您解答,skyhunter002为您答疑解惑如果本题有什么不明白可以追问,

原式=(X-Y)²/(X+Y)(X-Y)=(X-Y)/(X+Y)=(√3+1-√3+1)/(√3+1+√3-1)=2/2√3=1/√3=√3/3