## anonymous 5 years ago cos x/2 = cos π. find all solutions in the interval [0,2π)?

$cos(\pi)=-1$ so your equation is $cos(\frac{x}{2})=-1$ one solution is $\frac{x}{2}=\pi$ so $x=2\pi$ that is the only one in your interval. in fact it is not in your interval, so perhaps there is no solution!