Question

18 (cos+ i sin ) ¹8 6

Answer 1

Answer:

-1.

Step-by-step explanation:

1) according to the DeMoivre's theorem:

$1*(cos\frac{ \pi}{6} +isin\frac{ \pi}{6})^{18}=1^{18}(cos(18*\frac{ \pi}{6})+isin(18*\frac{ \pi}{6}))=cos3\pi +isin3\pi =cos\pi +isin\pi ;$

2) if cos(π)=-1 and sin(π)=0, then cosπ+i*sin(π)=-1.