求解数学题(a²-3)(a+2)-a(a²-a-2)

求解数学题(a²-3)(a+2)-a(a²-a-2)
求解数学题(a²-3)(a+2)-a(a²-a-2)

求解数学题(a²-3)(a+2)-a(a²-a-2)
化简=a3+2a2-3a-6-a3+a2+2a
=3a2-a-6
注：字母后面的数字表示次方.

答案是3a方-a-6