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The value of ( 1+ sin 2π 9+i cos 2π 9 1+ sin 2π 9-i cos 2π 9)^3 is

JEE Main 2023 — Mathematics Algebra

2023mcqhard

The value of (1+sin2π9+icos2π91+sin2π9−icos2π9)3{(\frac{1+\mathrm{sin}\frac{2\pi }{9}+i\mathrm{cos}\frac{2\pi }{9}}{1+\mathrm{sin}\frac{2\pi }{9}-i\mathrm{cos}\frac{2\pi }{9}})}^{3}(1+sin92π​−icos92π​1+sin92π​+icos92π​​)3 is

Official previous-year question

Held on 24 Jan 2023 · Verified 6 Jul 2026.

Options

  1. A

    −12(1−i3)\frac{-1}{2}(1-i\sqrt{3})2−1​(1−i3​)

  2. B

    12(1−i3)\frac{1}{2}(1-i\sqrt{3})21​(1−i3​)

  3. C

    −12(3−i)\frac{-1}{2}(\sqrt{3}-i)2−1​(3​−i)

  4. D

    12(3+i)\frac{1}{2}(\sqrt{3}+i)21​(3​+i)

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