(2-a)(4+2a+a²)-(3+a)(9-6a+a²)=
=8+4a+2a²-4a-2a²-a³-(27-18a+3a²+9a-6a²+a³)=
=8-a³-(a³-3a²-9a+27)=
=8-a³-a³+3a²+9a-27=
=-2a³+3a²+9a-19
Pri a=-2
-2(-8)+12-18-19= 16+12-18-10= -9
(2-a)(4+2a+a²)-(3+a)(9-6a+a²)=
=8+4a+2a²-4a-2a²-a³-(27-18a+3a²+9a-6a²+a³)=
=8-a³-(a³-3a²-9a+27)=
=8-a³-a³+3a²+9a-27=
=-2a³+3a²+9a-19
Pri a=-2
-2(-8)+12-18-19= 16+12-18-10= -9