[tex]\cos \theta = \dfrac 12\\\\\implies \theta = 2n\pi \pm \dfrac{\pi}3\\\\\text{For n =0 ~ \text{and}~ n=1}\\\\\\\theta = \dfrac{\pi}3 , \dfrac{5\pi}{3}\\\\\text{In degrees,}\\\\\theta = 60^{\circ} , ~ 300^{\circ}[/tex]
