(2a-b+c)的2次方-(a-2b+c)的2次方
问题描述:
(2a-b+c)的2次方-(a-2b+c)的2次方
答
(2a-b+c)的2次方-(a-2b+c)的2次方
=[(2a-b+c)+(a-2b+c)][(2a-b+c)-(a-2b+c)]
=(3a-3b+2c)(a+b)