Answer:
cos theta = adj / hyp is positive (+/+)
Step-by-step explanation:
In this open interval, the hypotenuse (radius) is always positive, whereas the adjacent side is positive and the opposite side negative.
in this interval:
sin theta = opp / hyp is neg (-/+)
cos theta = adj / hyp is positive (+/+)
tan theta = opp / adj = (-/+) : negative
