Answer
A. -1/2
B. -$\sqrt 3/2$
C. $1/\sqrt 3$
Work Step by Step
Check unit circle! If the value is negative simply add $2\pi$ to the answer until you get a value within the range of 0 $\leq$ r $\leq$ $2\pi$. If the value is higher subtract!
Someone from the community is currently working feverishly to complete this textbook answer. Don’t worry, it shouldn’t be long.