Question

X的7次方加上x的5次方加上1：应该怎么样分解因式？求大神帮助

x^7+x^5+1

Answer 1

解x^7+x^5+1 =(x^7+x^6+x^5)+(1-x^6) =x^5(x^2+x+1)+(1+x^3)(1-x)(1+x+x^2) =(x^2+x+1)(x^5-x^4+x^3-x+1)