已知P=[x^2/(x-y)]-[y^2/(x-y)],Q=(X-Y)(X-Y)-2Y(X+Y).小敏、小聪两人在X=2
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=X+Y,Q=(X-Y)(X-Y)-2Y(X+Y).小敏、小聪两人在X=2,Y=-1的条件下分别计算了P和Q的值.
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
已知P=x-y分之x平方-x-y分之y平方,Q=(x+y)平方-2y(x+y)小敏小聪两人在X=2,y=-1分别计算P和
[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013
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
已知p=(x²)/(x-y)-(y²)/(x-y)Q=(x+y)²-2y(x+y)小敏 小
已知4x=9y求(1)x+y/y (2)y-x/2x
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?