不用像上面两位那么麻烦,换位后很简单的。
(x+1)(x-1)(x^2-x+1)(x^2+x+1)
=【(x+1)(x^2-x+1)】【(x-1)(x^2+x+1)】 ……………… 换位
=(x^3+1)(x^3-1) …………平方差
=x^6-1
设 x^2+1=a
原式=(x^2-1)(a-x)(a+x)
=(x^2-1)(a^2-x^2)
=(x^2-1)*a^2-x^4+x^2
=(x^2-1)*(x^2+1)^2 -x^4+x^2
=(x^4-1)(x^2+1)-x^4+x^2
=x^6-1
(x+1)(x-1)(x^2-x+1)(x^2+x+1)
=(x²-1)[(x²+1)²-x²]
=x²(x²+1)²-x^4-(x²+1)²+x²
=x^6+2x^4+x²-x^4-x^4-2x²-1+x²
=x^6-1