Question 928162
{{{2cos(x)-1=0}}}
{{{2cos(x)=1}}}
{{{cos(x)=1/2}}}
{{{x=pi/3}}} and {{{x=(5/3)pi}}}
Both are {{{2pi}}}-periodic.
{{{x=pi/3+(2pi)k}}}
{{{x=(5/3)pi+(2pi)k}}}