The observations you made in the unit circle can help you determine the x‑ and y‑coordinates of special points on the circle without memorizing the circle. Analyze some of the patterns by completing the parts below.
a. Look at all the ordered pairs whose angles are of the form k pi/4, where k is an integer. What do you notice?
b.Now look at the ordered pairs whose angles are of the form k pi/6 or k pi/3. What do you notice about their coordinates?
c.How can you determine if the coordinates of a point are positive or negative?