i left this problem because it was hard for me

Question

An equation is given. (Enter your answers as a comma-separated list. Round terms to three decimal places where appropriate. If there is no solution, enter NO SOLUTION.)

2 cos 3θ = 1

(a) Find all solutions of the equation.
θ =

 

(b) Find the solutions in the interval [0, 2π).
θ =

 

Answer 1

Step 1:

The trigonometric equation is .

Find the solution of the equation.

General solution for : and

The solution of the equation and

Step 2:

Find the solution in the interval .

.

Substitute different values of .

The solution of the equation in the interval is

Solution :

(a) The solution of the equation and

(b) The solution of the equation in the interval is