试说明代数式x^3y^3-1/2x^2y+y^2-2x^3y^3+0.5x^2y+y^2+x^3y^3-2y^2-3的值
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)
试说明代数式x^3y^3-1/2x^2y+y^2-2x^3y^3+0.5x^2y+y^2+x^3y^3-2y^2-3的值
若x=-1/4,能否确定代数式(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)的值?
化简:(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方
【x-3y][x+y]-[x-2y][x +2y]-[x-y
[(3x+y)(x-y)-(2x+3y)(x-y)]*(x-y)
当2x-y/x+y=3时,求代数式2x-y/2x+2y+x+y/6x-3y的值.
已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y/2x-y的值
若X=负四分之一,能否确定代数式(2X-Y)(2X+Y)+(2X-Y)(Y-4X)+2Y(Y-3X)的值?
先化简再求值{(x-y)(x+y)-(x+y)(x-2y)}/y 其中xy的值是代数式{(3x-2y-7)^2+|2x+
已知x-y/x+y=2,求代数式2(x-y)/x+y + x+y/3(x-y)的值 快啊.