已知X^2+Y^2=4,x+y=2,求X^2008+Y^2008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-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-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=3分之一,y=-2分之一,求代数式x-(x+y)+(x+2Y)-(x+3y)+(x+4y)...-(x+2009y) 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 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,x^2-x=y^2-y,求x+y的值. 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 已知(x+2y)(2x-3y)=y(y-4x),试求x/y的值 已知x+y=a,2x-y=-2a,求[（x/y-y/x)/(x+y)-x(1/x-1/y)]/[(x+1)/y]的值 已知x^2+y^2+13-4x+6y=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2 已知2x-y分之x+y=2,求代数式4x-2y分之x+y-4x+4y分之2x-y的值 已知(2x-y)/(x+y)=2,求代数式(4x-2y)/(x+y)-(4x+4y)/(2x-y)的值. 已知(2x-y)/(x+y)=2,求代数式(4x-2y)/(x+y)-(4x+4y)/(2x-y)的值