1+2a+3a^2+4a^3+5a^4+6a^5+5a^6+4a^7+3a^82a^9+a^10
问题描述：
1+2a+3a^2+4a^3+5a^4+6a^5+5a^6+4a^7+3a^82a^9+a^10
急~有分
答
1+2a+3a^2+4a^3+5a^4+6a^5+5a^6+4a^7+3a^8+2a^9+a^10
=(1+a+a^2+a^3+a^4+a^5)+a(1+a+a^2+a^3+a^4+a^5)+a^2(1+a+a^2+a^3+a^4+a^5)+a^3(1+a+a^2+a^3+a^4+a^5)+a^4(1+a+a^2+a^3+a^4+a^5)+a^5(1+a+a^2+a^3+a^4+a^5)
=(1+a+a^2+a^3+a^4+a^5)^2
=((a+1)(a^4+a^2+1))^2
=(a+1)^2*(a^4+a^2+1)^2