x^2 -(4a-1)x+3a^2 -a

问题描述:

x^2 -(4a-1)x+3a^2 -a

x^2 -(4a-1)x+3a^2 -a=x^2 -(4a-1)x+a(3a-1)=(x+3a-1)(x+a)