若|X+Y-4|+(XY-1)^2=0,则X^2+Y^2=__________
1.已知:5x^2-4xy+y^2-2x+1=0,则(x-y)^2005+__________.
若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( )
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
若(2x-14xy-2y)除以(x-2xy-y)=4,则1/x-1/y=
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
若|x-2|+x²+1/4y²-xy=0 x= y=
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
若x,y满足x^+2y^-2xy+1=0,求xy的值
已知x-y=4xy,则2x+3xy-2yx-2xy-y
若1/x+1/y=2,则(2x-xy+2y)÷(3x+5xy+3y)
若x+y=10 xy=-1 则x²+y²=(x+y)²-2xy=