答：x/(x²-3x+1)=3两边取倒数：(x²-3x+1)/x=1/3x-3+1/x=1/3x+1/x=10/3两边平方：x²+2+1/x²=100/9x²+1/x²=82/9所以：x²/(x^4+x²+1)=1/(x²+1+1/x²)=1/(1+82/9)=9/9...