计算:(1/x-y-1/x+y)/2y/x^2-2xy+y^2,x=1+根号2,y=1-根号2
【(x-y)^3(x^1/2+y^1/2)^-3+3(x根号y-y根号x)】/(x根号x+y根号y)+(2xy根号xy-
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x=2+根号3,y=2-根号3,计算代数式(x+y/x-y-x-y/x+y)乘以(1/x^2-1/y^2)
x根号x+x根号y/xy-y^2)-(x+根号xy+y/x根号x-y根号)y
(x-y/x+2y)/(x^2-y^2/x^2+4xy+4y^2),其中x=1-根号2 y=根号2-2
{(x-y)/(根号x+根号y)}-(x+y-2倍根号xy)/(根号x-根号y)=?
计算:(2/3x根号下9x+6x根号下y/x)+(y根号下x/y-x的平方根号下1/x)=
根号2x-y-8+根号x+2y+1=0 求xy.
先化简再求值(x-y/1-x+y/1)÷x平方+2xy+y平方/2y,其中x=根号3+2,y=根号3
已知y根号[(x-1)/y]=负根号[(x-1)y],求xy的取值范围,并化简根号[2xy-(x^2+1)y]
(x+y)/(根号下x+根号下y)+2xy/(x根号下y+y根号下x)=______.