To determine the reference angle [tex]\( r \)[/tex] for a given angle [tex]\( \theta \)[/tex] in the first quadrant, we use the property that the reference angle for any angle [tex]\( \theta \)[/tex] in the first quadrant is the angle itself.
Given that [tex]\( \theta = \frac{\pi}{12} \)[/tex] lies in the first quadrant:
The correct equation to determine the reference angle [tex]\( r \)[/tex] is:
[tex]\[ r = \theta \][/tex]
Therefore:
[tex]\[ r = \frac{\pi}{12} \][/tex]
Thus, [tex]\( r = \theta \)[/tex] is the correct equation to determine the reference angle when [tex]\( \theta = \frac{\pi}{12} \)[/tex].
