(2x^2-4x-10xy)÷(?)=(1/2)x-1-(5/2)y
[-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y-
若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( )
已知x+y=-1,xy=-2,求代数式-5(x+y)+(x-y)+x(xy+y)的值
5xy平方-2x平方y+[3xy平方-(4xy-2x平方y-2x平方y)],其中x=-2,y=-1求值
先化简,再求值(x-y/x+y)^2÷(y-x/x^2+2xy+y^2)^2*1/x+y,其中x=-4,y=1
(1)x-y/x-2y÷x^2-y^2/x^2-4xy+4y^2
若1/x+1/y=2,则(2x-xy+2y)÷(3x+5xy+3y)
1/x-1/y=5求(-x+xy+y)/(2x+7xy-2y)
若1/x-1/y=3,求5x+2xy-5y/x-4xy-y的值
1/x-1/y=4,求分式(3x+xy-3y)/(x-2xy-y)
已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y=
(2x^2-4x-10xy)÷(?)=(1/2)x-1-(5/2)y