已知(x-2)∧2 y∧2=3,求y-x-搜答案-灵鹊做题网

(2x+y)/(x^2-2xy+y^2)X(x-y)=(2x+y)/（x-y）²*（x-y)=(2x+y)/（x-y）x-3y=0,x=3y(2x+y)/（x-y）=（6y+y）/（3y-y

x²+y²+2x－6y+10=0,（x²+2x+1）+(y²-6y+9)=0(x+1)²+(x-3)²=0x=-1y=3

[(x∧2+y∧2)-(x-y)∧2+2y(x-y)]÷4y=(2xy+2xy-2y^2)/(4y)=(2x-y)/2=10/2=5

2x-y/x+2y是(2x-y)/(x+2y)吧(2x-y)/(x+2y)=(2x/y-1)/(x/y+2)=(2X2/3-1)/(2/3+2)=1/3÷8/3=1/8

3x=8yx/y=8/3（1）x+y/y=x/y+1=8/3+1=11/3(2)2x+3y/x-2y分子分母同时除以y得=(2x/y+3)/(x/y-2)=(16/3+3)/(8/3-2)=(25/3

(x²-y²)/(x-y)=27/3(x+y)(x-y)/(x-y)=9x+y=9①x-y=3②①+②2x=12x=6①-②2y=6y=3y/x=3/6=1/2

X+Y分之X-Y等于3x=-2yX+Y分之2(x-y)减X+Y分之3X+Y=(-x-3y)/(x+y)=1

因为(x-y)/(x+y)=3,则(x＋y)/(x－y)＝1/3则5(x-y)(x+y)-(x+y)/2(x-y)＝5*3-1/(3*2)=15-1/6=89/6

f（x,y）＝3x＾2y＋y＾3－3x＾2－3y＾2＋2,下面求驻点坐标：f＆＃39；x＝6xy－6x＝0g①f＆＃39；y＝3x＾＋3y＾－6y＝09②由①,x＝0,或y＝1．把x＝0代入②y＾－2

（x+y)（x-y)-y^2+（x-y)^2-（6x^2y-2xy^2)÷2y=（x+y)（x-y)-y^2+（x-y)^2-2y（3x^2-xy)÷2y=（x+y)（x-y)-y^2+（x-y)^2

x+49=y49=y-x49=(y+x)(y-x)因为x,y是正整数所以y+x>0则y-x=49/(y+x)>0所以y+x>y-x>0而49=7×7=49×1若y+x=7y-x=7解得：x=0y=7x

1/2│x-2y│=-2│x-4│化简为|x-2y|=-4|x-4||x-2y|=-|4x-16|所以|x-2y|=0,-|4x-16|=0所以x-2y=0,x=2y4x-16=0,x=4所以y=2所

x-2y/2x+3y=3/44(x-2y)=3(2x+3y)4x-8y=6x+9y-2x=17yx/y=-17/2

（z-x)²-4（x-y）(y-z)=0z²-2xz+x²-4xy+4y²+4xz-4yz=0z²+x²+4y²+2xz-4xy-

(x-2y)/(3y-x)=2/33(x-2y)=2(3y-x)3x-6y=6y-2x5x=12y,代入原方程检验通过,故y/x=5/12

x-2y=3则：x=2y+3代入原式,原式=(4y+6+y-6)/(6y+9-y-9)=5y/5y=1

则二次根式有意义,得：2-X≥0,X-2≥0,∴X=2,∴Y=-3,Y^X=(-3)^2=9.Y^X的平方根为±3.

已知x+2+|y-3|=0

∵x+2≥0，|y-3|≥0且x+2+|y-3|=0，∴x+2=0，|y-3|=0，∴x+2=0，y-3=0，解得x=-2，y=3，当x=-2，y=3时，x2+y2+3=(-2)2+32+3=16=4

原式=x-x+x-x+……-x+(2-1+4-3+5-4+……+2008-2007-2009）y=0+(1×1004-2009)y=-1005y=1005/2