(x^2)/(x^4+x^2+1)=(x^2)/X^2*(X^2+1)+1=X^2+1+1=X^2+2又X^2-3X+1=0 X^2=3X-1 所以X^2+2=3X-1+2 =3X+1
x^2+1=3xx+1/x=3x^2+1/x^2+2=9x^2+1+1/x^2=8倒数为,原式=1/8