Class 11Mathematics1 Complex Numbers and Quadratic Equations: Complex NumbersDe Moivre's theorem and Roots of unity
EasyIf $z = \cos \theta + i \sin \theta$,then $z^r + (\bar{z})^r = $
- A$ \cos r \theta $
- B$ 2 \cos r \theta $
- C$ \sin r \theta $
- D$ 2 \sin r \theta $
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