2a^3+5a^2+2a-1=0因式分解
问题描述：
2a^3+5a^2+2a-1=0因式分解
答
2a^3+4a^2+2a+a^2-1=0
2a(a^2+2a+1)+(a+1)*(a-1)=0
2a*(a+1)^2+(a+1)*(a-1)=0
(a+1)(2a^2+2a+a-1)=0
(a+1)(2a^2+3a-1)=0
a=-1