Step 1 :

The trigonometric equation is $\"\"$ and the interval is $\"\"$

Factorize the quadratic equation.

$\"\"$

Since the range of the inverse tangent function is $\"\"$ , obtain two solutions in the interval $\"\"$ .

$\"\"$

If $\"\"$ , then, the general solution is $\"\"$ , where $\"image\"$ is an integer.

The general solutions are $\"\"$ , where $\"image\"$ is an integer.

If $\"image\"$ , then

$\"\"$ ,

If $\"image\"$ , then

$\"\"$ ,

If $\"image\"$ , then

$\"\"$ .

The solutions are $\"\"$ , $\"\"$ , and $\"\"$ in the interval $\"\"$ .