已知x+4y-2x+8y+5=0,求x^4-y^4/2x+xy-y·2x-y/xy-y÷(x+y/y)的值.
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知x+4y-2x+8y+5=0,求x^4-y^4/2x+xy-y·2x-y/xy-y÷(x+y/y)的值.
已知X+Y=2XY,求4X-5XY+4Y 除以X+XY+Y 的值
已知x²+y²-2x+4y+5=0,求X^4-y^4/2x^2+xy-y²·2x-y/xy
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
已知x,y>0 2x+y+3=xy 求5x+4y最小值
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知5x-4y=0且xy不等于0,求x^2+y^2/x^2-y^2-x+y/x-y的值
已知x^3+xy^2+x+x^2y+y^3+y=0,求5x-6y/3x+4y的值.
已知x+y=5,xy=2,求5x+4y-3y-2y+xy的值
已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的
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*