$\"\"$

The trigonometric equation is $\"\"$ .

Consider $\"\"$ .

$\"\"$ .

The general solution of $\"\"$ is $\"\"$ , where $\"\"$ is an integer.

$\"\"$

Divide each side by 2.

$\"\"$ .

Thus, the general solution is $\"\"$ , where $\"\"$ is an integer.

$\"\"$

The general solution is $\"\"$ , where $\"\"$ is an integer.