Which angle is an x-intercept for the function y = cos (1/2x)

For the function

y = cos (1/2 x)

The x-intercept can be calculated by equating the function to zero and solving for x. So,

y = cos (1/2 x) = 0

1/2 x = arc cos 0

1/2 x = 90° + 180°n

x = 2 (90° + 180°n)

x = 180° + 360°n

or converting to radians

x = (180° + 360° n) (π/180°)

x = π + 2π n

where n is any whole number

if n = 0

x = π

Therefore, the x-intercept is π or π+2π n