The value of \[\sum\limits_{r=1}^{8}{\left( \sin \frac{2r\pi }{9}+i\co – McqOptions

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1.	The value of \[\sum\limits_{r=1}^{8}{\left( \sin \frac{2r\pi }{9}+i\cos \frac{2r\pi }{9} \right)}\]is
A.	\[-1\]
B.	1
C.	\[i\]
D.	\[-i\]
Answer» E.

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