Answer:
72(cos 75° + isin 75°)
Step-by-step explanation:
[tex]\boxed{z_1\times z_2=r_1\cdot r_2(cos(\theta_1+\theta_2)+isin(\theta_1+\theta_2))}[/tex]
[tex]z_1\times z_2=24\times3(cos(315^o+120^o)+isin(315^o+120^o))[/tex]
[tex]=72(cos\ 435^o+isin\ 435^o)[/tex]
[tex]=72(cos\ 75^o+isin\ 75^o)[/tex]
