2a（a+1）-（a+2）（a-2）原式=2a²+2a-(a²-4) =2a²+2a-a²+4 =a²+2a+4 =-1+4 =3 【中学生数理化】团队为您解答!祝您学习进步不明白可以追问!满意请点击下面的【选...