Question

cos x/6 = корень из 2/2

Answer 1

$Cos\frac{x}{6}=\frac{\sqrt{2}}{2}\\\\\frac{x}{6}=+-arcCos\frac{\sqrt{2} }{2}+2\pi n,nez\\\\\frac{x}{6}=+-\frac{\pi }{4}+2\pi n,nez\\\\x=+-\frac{3\pi }{2}+12\pi n,nez$