### Home > CCA2 > Chapter 8 > Lesson 8.1.1 > Problem8-16

8-16.
1. Without a calculator, find two solutions 0° ≤ θ < 360° that make each of the following equations true. Homework Help ✎

1. cos θ =

2. tan θ = −1

3. sin θ =

4. cos θ = −

Draw a unit circle.

$\text{The cosine is where the }x\text{-value (red line) is }\frac{1}{2}.$