已知x=2009,y=2010.化简(x+y)*(x^2+y^2/x^4-y^4)
已知x=2009,y=2010.化简(x+y)*(x^2+y^2/x^4-y^4)
已知4x=9y求(1)x+y/y (2)y-x/2x
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
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=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=3分之一,y=-2分之一,求代数式x-(x+y)+(x+2Y)-(x+3y)+(x+4y)...-(x+2009
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
已知x^2+4y^2-4x+4y+5=0,求(y^4-x^4)/(y-2x)(x+y)*2x-y