a³-9b+9a+a²b因式分解
问题描述:
a³-9b+9a+a²b因式分解
答
a³-9b-9a+a²b
=a³-9a+a²b-9b
=a(a²-9)+b(a²-9)
=(a+b)(a²-9)
=(a+b)(a+3)(a-3)