若x2-3x+1=0,求分式x2/(x^4+x2+1)的值是 求大神幫忙!

若x2-3x+1=0,求分式x2/(x^4+x2+1)的值是 求大神幫忙!

對分母x^4+x^2+1進行因式分x^4+x^2+1=x^4+2x^2+1-x^2=(x^2+1)^2-x^2=(x^2+x+1)(x^2-x+1),又因為x^2-3x+1=0,所以x^2=3x-1.這樣分母就化為(3x-1+x+1)(3x-1-x+1)= 4x·2x=6x^2.x^2/6x^2=1/6,所以答案是1/6.