What are the coordinates for the point p(5π6) where p(θ)=(x,y) is the point where the terminal arm of an angle θ intersects the unit circl?

1 Answer
Dec 31, 2017

p(5π6)=(32,12)

Explanation:

5π6 has reference angle π6 because π5π6=π6.

So we know that:
cos(5π6)=cos(π6)=32
sin(5π6)=sin(π6)=12

Since 5π6 QII, we know that cos(5π6)<0 and sin(5π6)>0.

Combining what we know, we have that p(5π6)=(32,12).

I recommend memorizing the entire Unit Circle as it's not that difficult and is extremely useful.