### Home > INT3 > Chapter 12 > Lesson 12.1.2 > Problem12-25

12-25.
1. For each of the following equations, what are the solutions that lie in the domain 0 ≤ x < 2π? Homework Help ✎

1. 2sin(x) – 1 = 0

2. 2cos(x) = –

3. 2sin(x) =

4. cos(x) = 1

$\text{For the equation to be true, sin(\textit{x}) must= }\frac{1}{2}.$

You can either draw a unit circle to find all possible solutions, or solve the equation graphically.

In what quadrants is cos(x) negative?

$\text{When does sin(\textit{x})= }\frac{\sqrt{2}}{2}?$

Picture a unit circle. At what angle is the adjacent side the same length as the hypotenuse?