Question

$cos( x \2 - \pi \div 6) = \sqrt{3 \div 2)$
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Answer 1

$\cos( \frac{x}{2} - \frac{\pi}{6} ) = \frac{ \sqrt{3} }{2}$

1 случай:

$\frac{x}{2} - \frac{\pi}{6} = \frac{\pi}{6} + 2\pi n \\ \frac{x}{2} = \frac{2\pi}{6} + 2\pi n \\ x = \frac{2\pi}{3} + 4\pi n, nєZ$

2 случай:

$\frac{x}{2} - \frac{\pi}{6} = \frac{11\pi}{6} + 2\pi n \\ \frac{x}{2} = \frac{12\pi}{6} + 2\pi n \\ x = 4\pi + 4\pi n\\x=4πn, nєZ$