Question

Prove that
${ \cos }^{2} x + { \cos}^{2} (x + \frac{\pi}{3} ) + { \cos }^{2} (\pi - \frac{2\pi}{3} ) = \frac{3}{2}$
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Answer 1

Hey mate,

see the attached photo

Give ❤️

Answer 2

Hence proved thx ......