Texas Instruments TI-83 PLUS - Manual (Page 102)

TI-83 Plus Math, Angle, and Test Operations 99
r (Radians)
r (radians) designates an angle or list of angles as radians, regardless of
the current angle mode setting. In Degree mode, you can use r to convert
radians to degrees.
value r
Degree mode
8 DMS
8 DMS (degree/minute/second) displays answer in DMS format. The mode
setting must be Degree for answer to be interpreted as degrees, minutes,
and seconds. 8 DMS is valid only at the end of a line.
answer 8 DMS