(3a+1)(2a-3)-6(a-1)(a+2)
问题描述：
(3a+1)(2a-3)-6(a-1)(a+2)
答
(3a+1)(2a-3)-6(a-1）（a+2）
展开试式或得：6a^2-9a+2a-3-6(a^2+2a-a-2)=6a^2-9a+2a-3-6a^2-12a+6a+12=-13a+9=-3*13+9=-30
答
(3a+1)(2a-3)-6(a-1)(a+2)
=6a²-9a+2a-3-6(a²+2a-a-2)
=6a²-9a+2a-3-6a²-6a+12
=-13a+9
答
(3a+1)(2a-3)-6(a-1)(a+2)
=6a^2-7a-3-6(a^2+a-2)
=6a^2-7a-3-6a^2-6a+12
=-13a+9