a³(x-y)-3a²b(y-x)因式分解为

a³(x-y)-3a²b(y-x)因式分解为
a³(x-y)-3a²b(y-x)因式分解为

a³(x-y)-3a²b(y-x)因式分解为
a³(x-y)-3a²b(y-x)
=a³(x-y)+3a²b(x-y)
=a²（x-y）(a+3b)
如果本题有什么不明白可以追问,

a³(x-y)-3a²b(y-x)
=a²[a(x-y)+3b(x-y)]
=a²(x-y)(a+3b)