已知x^2+1/x^2=23,试求x+1/x与x-1/x的值

已知x^2+1/x^2=23,试求x+1/x与x-1/x的值
已知x^2+1/x^2=23,试求x+1/x与x-1/x的值

已知x^2+1/x^2=23,试求x+1/x与x-1/x的值
x2+1/x2=23
x2+1/x2+2=25
(X+1/x) 2=52
X+1/x=5
x2+1/x2-2=21
(X-1/x) 2=21
X-1/x=√21

x+1/x=5，x-1/x=根号下21

5和根号21