3x^2-xy÷9x^2-6xy+y^2 等于多少
由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?
2x(x²y-xy²)+xy(xy-x²)]÷x²y等于多少
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
3y/2x+2y + 2xy/x²+xy等于多少过程
若x-y=5.xy=6,x^2y+xy^2等于多少
3xy+xy+2x²y+yx²+3x²y等于多少
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)
2x平方+3xy+2y平方等于多少
若1/x+1/y=3,4y-2xy-4x/3x+xy-3x等于多少
1/x-1/y=3 求x-3xy-y/2x-xy-2y 等于多少
如果1\x-1\y=2,那么3x+5xy-3y\x-xy-y等于多少
x平方-2x除以2y-xy等于多少,