jee-main 2020 Q52

jee-main · India · session2_02sep_shift1 Complex Numbers Arithmetic Trigonometric/Polar Form and De Moivre's Theorem
The value of $\left( \frac{1 + \sin\frac{2\pi}{9} + i\cos\frac{2\pi}{9}}{1 + \sin\frac{2\pi}{9} - i\cos\frac{2\pi}{9}} \right)^{3}$ is
(1) $\frac{1}{2}(1 - i\sqrt{3})$
(2) $\frac{1}{2}(\sqrt{3} - i)$
(3) $-\frac{1}{2}(\sqrt{3} - i)$
(4) $-\frac{1}{2}(1 - i\sqrt{3})$
The value of $\left( \frac{1 + \sin\frac{2\pi}{9} + i\cos\frac{2\pi}{9}}{1 + \sin\frac{2\pi}{9} - i\cos\frac{2\pi}{9}} \right)^{3}$ is\\
(1) $\frac{1}{2}(1 - i\sqrt{3})$\\
(2) $\frac{1}{2}(\sqrt{3} - i)$\\
(3) $-\frac{1}{2}(\sqrt{3} - i)$\\
(4) $-\frac{1}{2}(1 - i\sqrt{3})$