Question

cos x/6 = корень из 2/2

Answer 1

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