Question

Question #30286

Answer 1

Because the `cos` function repeats its values every `360` degrees or `2pi` radians.

Explanation:

This can be seen clearly in a graph of `f(x) = cos(x)` graph{cos(x) [-10.205, 9.785, -4.33, 5.67]}

The graph above is in radians so the values are seen repeating every `2pi` units (6.3), which is the same as 360 degrees.