若x加x分之1等于3,求x的4次方加x的2次方加1分之x的2次方的值

2024-12-26 22:20:18
推荐回答(1个)
回答1:

x+1/x=3
(x+1/x)^2=9
x^2+1/x^2+2=9
x^2+1/x^2=7
x^2/(x^4+x^2+1)
=1/(x^2+1/x^2+1)
=1/(7+1)
=1/8