作业帮-2(ab-3a²)-[2b²-(5ab+a²)+2ab] ,
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/02 08:01:46
![-2(ab-3a²)-[2b²-(5ab+a²)+2ab] ,](/uploads/image/z/3024245-29-5.jpg?t=-2%28ab-3a%26%23178%3B%29-%5B2b%26%23178%3B-%285ab%2Ba%26%23178%3B%29%2B2ab%5D+%2C)
-2(ab-3a²)-[2b²-(5ab+a²)+2ab] ,
-2(ab-3a²)-[2b²-(5ab+a²)+2ab] ,
-2(ab-3a²)-[2b²-(5ab+a²)+2ab] ,
-2(ab-3a²)-[2b²-(5ab+a²)+2ab]
=-2ab+6a²-[2b²-5ab-a²+2ab]
=-2ab+6a²-2b²+5ab+a²-2ab
=ab+7a²-2b²