### Home > PC > Chapter 4 > Lesson 4.1.4 > Problem4-55

4-55.

Study the diagram of the unit circle below right, in which VW $= 0.62$.

1. Find $\text{sin }θ$.

In a unit circle, what is the radius?

2. Find $\text{cos }θ$.

You have two sides of a right triangle. Find the third side, which is the $x$-coordinate.

3. α is another angle with the same sine as $θ$, but a different cosine. What quadrant is $α$ in?

In Quadrant III, sine and cosine are both negative.
In which quadrant is sine negative and cosine positive?

4. $β$ is another angle with the same cosine as $θ$, but a different sine. What quadrant is $β$ in?

In which quadrant is cosine negative and sine positive.