Determine the reference angle, in radians, associated with the given angle. Write the exact answer. Do not round,0=13л12

An angle's reference angle is the measure of the smallest, positive, acute angle formed by the terminal side of the angle and the horizontal axis.
We need to go back 13 pi/ 12 - pi
13 pi/12 - 12pi/2 = 1pi/12
The reference angle is pi/12