Find all solutions of the equation 2cosx1=0.\displaystyle {2}{\cos{{x}}}-{1}={0}.
The answer is A+Bkπ\displaystyle {A}+{B}{k}\pi and C+Dkπ\displaystyle {C}+{D}{k}\pi where k\displaystyle {k} is any integer, 0<A<C<2π\displaystyle {0}<{A}<{C}<{2}\pi,

A=\displaystyle {A}=   , B=\displaystyle {B}=   ,
C=\displaystyle {C}=   , D=\displaystyle {D}=   .