合并同类项 6a²-[7a²-3a-(a²-4a)]

问题描述:

合并同类项 6a²-[7a²-3a-(a²-4a)]

6a²-[7a²-3a-(a²-4a)]
= 6a²-[7a²-3a-a²+4a]
= 6a²-[6a²+a]
= 6a²-6a²-a
=-a