x方-y方/x方y+xy方=(x+y)(x-y)/[xy(x+y)]=(x-y)/xy=[(√3+1)-(√3-1)]/[(√3+1)(√3-1)]=2/2=1
原式=（x+y）*（x-y）/xy(x+y)=(x-y)/xy=1
原式化简为x-y/xy,带入计算结果为根号2/2-1/2
