3(a³-a²+1/2ab²)-1/2(6a³+4a²b+3ab²)

问题描述:

3(a³-a²+1/2ab²)-1/2(6a³+4a²b+3ab²)

3(a³-a²+1/2ab²)-1/2(6a³+4a²b+3ab²) =3a³-3a²+3/2ab²-3a³-2a²b-3/2ab²=-3a²-2a²b=-a²(3+2b)