Answer
$\dfrac{1}{2}$
Work Step by Step
$\cos{(\theta+ 360^{\circ} k)} = \cos{\theta}$
$\therefore \cos{(\theta+ 360^{\circ} k) }= \cos{(60^{\circ}+360^{\circ})} = \cos{60^{\circ}}$
$\cos{60^{\circ}} = \boxed{\dfrac{1}{2}}$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.