1.已知x-y=2,x^2+y^2=4,求x^2004+y^2004的值

已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y 已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y² 已知x*x+4x+y*y-2y+5=0,则x*x+y*y=? 已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 1.(x-2y)(x+2y)-(x平方+y)(x平方-y) 2.(2x-y)(y+2x)-(2y+x)(2y-x)3.已知：x+y=6,x平方-y平方=48,求x,y的值4.x平方-2x分之x+2 -- x平方-4x+4分之x-1 1.已知:x-2y=3,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]除4x 的值 已知:【(x²+y²)-(x-y)²+2y(x-y)】/4y=1,求4x/4x²-y²-1/2x+y 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 已知(x+2y)(2x-3y)=y(y-4x),试求x/y的值 已知x=3分之一,y=-2分之一,求代数式x-(x+y)+(x+2Y)-(x+3y)+(x+4y)...-(x+2009y) x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 1.已知2x+y=4,求这个整式[(x+y)^2-(x-y)^2-2y(x-1/2 y)]÷4y的值 已知f(x+y,y/x)=x^2-y^2,则f(x,y)= 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y