已知x=84,y=2.56,求x+y-2根号xy/根号x-根号y,
已知x=84,y=2.56,求x+y-2根号xy/根号x-根号y,
已知y=根号(x-8)+根号(8-x)+18,求代数式[(x+y)/(根号x+根号y)]-2xy/(x根号y-y根号x)
已知y=根号1-x+根号x-1+3,求根号x+根号y分之x+2根号xy+y+根号x-根号y分之一的值
已知,x=484,y=2.56,求x+y-2倍根号xy、根号x-根号y
已知根号x(根号x-根号y)=根号xy+3y,求(3x-y)分之2x+3倍根号xy-y 的值
代数式求值.已知x=2,y=根号3,求 (根号x-根号y)/(根号x+根号y)+(根号x+根号y)/(根号x-根号y)
已知x,y为正数,且根号x(根号x+根号y)=3根号y(根号x+5根号y),求:(2x+根号xy+3y)/(x+根号xy
已知当x=8,y=18,求(x+y)/(根号x-根号y)-(2xy)/(x根号y-y根号x)
已知x平方+y平方-2y+1=0,求(根号x+根号y+3)/((根号xy+y)(3根号x+根号y))
已知根号x+根号y=根号5,根号xy=根号15-根号3,求x+y的值
已知x+y=3,xy=6,.求根号x/y+根号y/x
已知正实数x y满足x-根号xy-2y=0求 x+3根号xy+2y/2x-2根号下xy-y