当x=0.3,y=0.7时,求分式x^3-x^2-xy^2+y^3/-x^4+2x^2y^2-y^4的值,
当x=3,y=7时,求分式(xy+2y)-(x+2)/x^2-4的值
当x/y=3/4时,求分式(xy+y^2)/(x^2-xy)的值
1.当x=0.3,y=0.7时,求分式x^3-x^2-xy^2+y^3/-x^4+2x^2y^2-y^4的值.2.当a=
当x=0.3,y=0.7时,求分式x^3-x^2-xy^2+y^3/-x^4+2x^2y^2-y^4的值,
若(y-x)/xy=3,求分式(2x+3xy-2y)/(x-2xy-y)的值
已知x-y/xy=3,求分式2x+3xy-2y/x-2xy-y的值.
初中数学分式已知x/y=2,求(x*x-xy+3y*y)/x*x+xy+6y*y的值
当x-y=1时,求x^4-xy^3-x^3y-3x^2y+3xy^2+y^4的值
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知1/x+1/y=3,求分式3x-2xy+3y/x+xy+y的值
1/x+1/y=3.求分式3x-2xy+3y/x+xy+y的值
已知,1/x+1/y=5.,求分式3x+xy+3y/x-2xy+y的值