(1)x(x-1)-(x^2-y)=-2,求{(x^2)+(y^2)}/2-xy
x+y=1,xy=-1/2,求x(x+y)(x-y)-x(x+y)2
已知x+y=-1,xy=-2,求代数式-5(x+y)+(x-y)+x(xy+y)的值
(1)x(x-1)-(x^2-y)=-2,求{(x^2)+(y^2)}/2-xy
x(x-1)-(x平方-y)=-3,求x平方+y平方-2xy
1/x-1/y=3,求2x+3xy-2y/x-y
已知3/(x-y)=1/xy 求(-x-2xy+y)/ (2x+3xy-2y)
已知:xy+x=-1,xy-y=-2,求多项式-x-[2y-2(xy+x)的平方+3x]+2[x+(xy-y)的平方]的
已知x-y=3,xy=1,求(-2x+2x+3y)-(3xy+2y-2x)-(x+4y+xy)
已知x+y=-1,xy=-2,求代数式-5(x+y)+(x-y)+2(xy+y)的值
已知X+Y=-1,xy=-2,求代数式-5(x+y)+(x-y)+(xy+y)的值
已知:x-y=1,xy=-2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
x-y=1,xy=2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值