4x^2+9y^2-4x-6y+2=0,求1/√xy

已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 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^2+y^2+x^2y^2-4xy+1=0 求(x-y)^2008-(xy)^2008 已知X²+Y²+X²Y²-4XY+1=0 求:（X-Y)^2008-(XY)^2 若 |x^2-3xy-4y^2|+2√(x^2+4xy+4y^2-1)=0 求3x+6y的值 已知|x²-2xy-8y²|+2√x²-4xy+4y²-1=0,求3x+6y的值 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* 已知4x^2+y^2-4xy-12x+6y+9=0,求x,y的关系 若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 x^+2xy+y^+4=16 x^-2xy+y^=16 求(3xy+6y^)+|x^-(2xy+2y^-3x^)|的值 已知：x-y=1,xy=-2.求：(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值