课堂上,李老师给大家出了这样一道题：当x=3,5-2倍根号2,7+根号3时,求代数式x的平方-2x+1/x的平方-1除

当x=3x的平方-2x+1/x的平方-1=(x-1)(x-1 )/(x+1)(x-1 )=(x-1 )/(x+1)=3-1/(3+1)=1/2x=5-2倍根号2x的平方-2x+1/x的平方-1=(x-1)(x-1 )/(x+1)(x-1 )=(x-1 )/(x+1)=4-2根号2/6-2根号2 ...