您好: x^4-7x^2+1=x^4-2x^2+1-5x^2=(x^2-1)^2-(√5x)^2=(x^2-1+√5x)(x^2-1-√5x)=(x^2+√5x-1)(x^2-√5x-1)不明白,可以追问如有帮助,记得采纳,谢谢 祝学习进步!