已知:P=x²/x-y - y²/x-y,Q=(x+y)²-2y(x+y).
已知P=x²/x-y-y²/x-y,Q=(x+y)²-2y(x+y),小红、小华两人在x=
数学题已知p=x^/x-y-y^/x-y,q=(x+y)^-2Y(X+Y),
已知p=(x²)/(x-y)-(y²)/(x-y)Q=(x+y)²-2y(x+y)小敏 小
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
设P={y[y=-x²+1,x∈R}.Q={y[y=2^x,x∈R},则( )
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知2x-y=10,求代数式[(x²+y²)-(x-y)²+2y(x-y)]÷4y的值?
已知:P=(x-y分之x^2)-(x-y分之y^2),Q=(x+y)^2-2y(x+y),小敏小聪两人在X=1,y=-1
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
2.(x+y)²(x-y)²-(x-y)(x+y)(x²+y²)
设集合P={x-y,x+y,xy},Q={x²十y²,x²-y²,0},若P=Q