Question

Find the measures of two angles, one positive and one negative that are coterminal with pi/5

Answer 1

To find coterminal angles for an angle, β, given in radians use the following formula:
coterminal angle = β + 2πk
where k is an integer {..., -3, -2, -1, 0, 1, 2, 3, ...}
Negative Coterminal Angle: k = -1
NCA = π/5 + 2π(-1)
= -9π/5
Positive Coterminal Angle: k = 1
PCA = π/5 + 2π(1)
= 11π/5
The following answers are just one of many possible answer... you have infinite number of choices for k.

`NCA = (-9 \pi )/(5)`

`PCA= (11 \pi )/(5)`