### Home > PC > Chapter 4 > Lesson 4.3.1 > Problem 4-128

4-128.

Find the exact value of each of the following trig expressions.

sin

1. Plot the point on a unit circle.

2. Find the sides of this special triangle.

3. Be careful of the signs!

4. Write the answer.

cos

bring the point back to .

cot

Wrap clockwise because of the negative sign.

sec

Since the sec\theta; is, this would be undefined because the at .