已知2x的平方y与-2分之1x的2m次方y的3n次方-搜答案-大师作文网

[（x的平方+y的平方）-（x-y)的平方+2y(x-y)]/4y=1(x²+y²-x²+2xy-y²+2xy-2y²)/4y=1(4xy-2y

x-3y=0x=3y(2x+y)/(x^2-2xy+y^2)÷1/(x-y)=(2x+y)/(x-y)^2÷1/(x-y)=(2x+y)/(x-y)^2*(x-y)=(2x+y)/(x-y)=(2*3

3x^2+xy-2y^2=(3x-2y)(x+y)=0x=-2y/3,或x=-y但由于你要求的式子中分母里有X平方-Y平方x=-y舍去其他就代入吧

够详细了吧

1）2003（x+y)≥0|1/2x+3/2y-1|≥02003（x+y)平方与|1/2x+3/2y-1|的值互为相反数,则有2003（x+y)+|1/2x+3/2y-1|=0则有2003（x+y)=

|x-2|与3y的平方互为相反数可以推出|x-2|+(3y)^2=0进一步推出X=2,Y=0则3分之2-y+3分之1x-9y=2/3-0+2/3=0

|x-2|+3y²=0∴x=2y=0∴(2x-y)/3+(x-9y)/3=(2×2-0)/3+(2-9×0)/3=4/3+2/3=2

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)

2x-y+1的绝对值+（3x+2分之3y）平方=0则2x-y+1=03x+3y/2=0,则2x-y=-1①2x+y=0②①+②,得4x=-1,则x=-1/4①-②,得-2y=-1,则y=-1/2x+y

x/y=1/2y=2x(x^2+2xy+y^2)/(x^2-xy+y^2)=(x^2+2x*2x+(2x)^2)/(x^2-x*2x+(2x)^2)=9x^2/3x^2=3

y分之x=2分之1y=2x所以原原式=(x²-2x²-8x²)分之（x²＋4x²＋4x²）=-9分之9=-1

【1】∵y=x²-mx+(m²+1)/2的判别式=m²-2(m²+1)=-m²-2∵m²≥0∴-m²-2=-(m²+2)

y=[(x+1)²/(x+1)(x-1)]÷[(x+1)/x(x-1)]-x+1=(x+1)/(x-1)×x(x-1)/(x+1)-x+1=x-x+1=1所以y和x的取值无关

x的平方+2xy+y的平方分之x的平方-y的平方=(x+y)(x-y)/(x+y)²=(x-y)/(x+y)∵x+y=2,x-y=1∴原式=1/2

2x-y+1=0;y²+4y+4=0；（y+2）²=0;y=-2;2x=y-1;2x=-3;x=-3/2;1-x-2y分之x-y÷x的平方-4xy+4y=1-(x-y)/(x-2y

解(1)：最简公分母是6(x+5)3分之x=x/3=2x(x+5)/[6(x+5)]6分之1-x=(1-x)/6=(1-x)(x+5)/[6(x+5)]x+5分之x平方-x=(x²-x)/(

(4-x的平方)分之(x的平方-2x)=x(x-2)/-(x+2)(x-2)=-x/(x+2)通分（y-x)分之1=2(x+y)(y-x)分之2(x+y)与（2x+2y）分之1=2(x+y)(y-x)

x的平方-64y的平方分之2x-x-8y分之1=[2x-(x+8y)]/(x-8y)(x+8y)=(x-8y)/(x-8y)(x+8y)=1/(x+8y)

y分之x=2分之1y=2x所以原原式=(x²-2x²-8x²)分之（x²＋4x²＋4x²）=-9分之9=-1

x-y分之2x的平方-y-x分之x的平方-4xy+x-y分之2y的平方-x的平方=2x/(x-y)-(x²-4xy)/(y-x)+(2y-x²)/(x-y)=(2x+x²