计算：①-5(a²-2)-2(3a²+5) ②-2（ab-3a²）-[2b²-（5ab+a²）+2ab]
问题描述：
计算：①-5(a²-2)-2(3a²+5) ②-2（ab-3a²）-[2b²-（5ab+a²）+2ab]
答
解-5(a²-2)-2(3a²+5)=(-5a²-6a²)+(10-10)=-11a²-2(ab-3a²)-[2b²-(5ab+a²)+2ab]=-2ab+6a²-(2b²-5ab-a²+2ab)=-2ab+6a²-(2b²-a²-3ab)=(-2ab+3a...