x+y=32,x²-y²=48
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知x+y=1,xy=-二分之一,求x(x+y)(x-y)-x(x+y)²
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
[(y-2x)(-2x-y)-4(x-2y)²]*2y,其中x=1,y=2
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
x²+xy/(x-4y)(x+y),其中x=4,y=-1
{(x+2y)(x-2y)+[2(x-y)]²}÷6x=?
已知P=x²/x-y-y²/x-y,Q=(x+y)²-2y(x+y),小红、小华两人在x=
已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的
[2x²-(x+y) (x-y)] [(-x-y) (y-x)+2y²] 其中x=1,y=2
已知集合A={(x,y)|x²+y²≤1.x.y∈R},B={(x,y)||x|+|y|≤2.x.y
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)