Question

八年级数学，急求！！好答案追加高悬赏！

Answer 1

x/(x²-3x+1)=2
所以1/(x-3+1/x)=2
即x-3+1/x=1/2
x+1/x=7/2

所以原式=1/(x²+1+1/x²)
=1/[(x+1/x)²-1]
=1/[(7/2)²-1]
=4/45

Answer 2

x/(x^2-3x+1)=2
(x^2-3x+1)/x=x-3+1/x=1/2
x+1/x=3+1/2=7/2

x^2/(x^4+x^2+1)
=1/[(x^4+x^2+1)/x^2]
=1/(x^2+1+1/x^2)
=1/[(x+1/x)^2+1]
=1/[(7/2)^2-1]
=4/45