若x^2+y^2+2x+2y+1=0则x+y的取值范围是?

若x+y=1,x不等于0则x+(2xy+y^2)/x/(x+y)/x= x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 若x,y满足|x-y+1|+(x+y+3)^2=0则x^2-y^2= 若x,y满足|2x-y-3|+|3x+2y+1|=0,则x= y= 若|x+y+1|+(x-2y)的平方=0,则x+2y=? 若y=x(x-1)(x-2)(x-3),则y′（0）= 若f(x+y,y/x)=x^2-y^2,则F(X,Y)= 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 若x*x+y*y=x+y-1/2,求x,y的值如题 若|x+y-1|+（x-y-2)²=0,求代数式（x+2y)(x-2y）-（2x-y)(-y-2x)的值. 已知x属于R,y>0,集合A={x|x*x+x+1,-x,-x-1},集合B={-y,-y/2,y+1}若A=B,则x*x+y*y的值为 若3x-5y=0,则x+y/x=（）,x-y/y=（）,2x-3y/2x+3y=( ) 若2x=3y,则(x*x+y*y)/x*x=? 若x+y=4,则多项式1/2(x+y)+4(x-y)-3（x-y）-3/2(x+y)-x+y值是（） 若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*y)的值 若实数X,Y满足X²+Y²+4X-2Y +1=0,则X²-6X+Y²-2Y的最大值是多少