Step 1: \

The trigonometric equation is $\"\"$ .

Find the solution of the equation.

$\"\"$

General solution for $\"\"$ : $\"\"$

$\"\"$

The solution of the equation $\"\"$

Step 2 :

Find the solution in the interval $\"\"$ .

No solution of the equation in the interval $\"\"$ .

Solution :

(a) The solution of the equation $\"\"$

(b) No solution.