A) \[-1\]
B) \[-i\]
C) \[\frac{1+i\sqrt{3}}{2}\]
D) \[\frac{1-i\sqrt{3}}{2}\]
E) \[-i\]
Correct Answer: E
Solution :
10th term is, \[{{(\cos \theta +i\sin \theta )}^{9}}\] \[\Rightarrow \] \[\cos 9\theta +i\sin 9\theta \] For \[\theta =\pi /6\] 10th term \[=\cos \frac{9\pi }{6}+i\sin \frac{9\pi }{6}\] \[=\cos \frac{3\pi }{2}+i\sin \frac{3\pi }{2}=-i\]You need to login to perform this action.
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