已知x-y=-2,求(x²+y²)²-4xy(x²+y²)+4x
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知X²+Y²+X²Y²-4XY+1=0 求:(X-Y)^2008-(XY)^2
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知x²+y²-2x+4y+5=0,求X^4-y^4/2x^2+xy-y²·2x-y/xy
已知x+y=1,xy=-二分之一,求x(x+y)(x-y)-x(x+y)²
已知2x-y=10,求式子[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y (4xy-2y²)/4
已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.
已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
已知2x+y=0,求x-2y/x²+xy*(x²-y²)/x²-4xy+4y
已知2x+y=0,求x-2y/x²+xy乘(x²-y²)÷x²-4xy+4y
已知实数x,y满足x²+y²-xy+2x-y+1=0 求x y
已知x,y满足x(+1)-(x²+2y)=1,求x²+4xy+4y²-2x+4y的值.