$\"\"$

\

Find the derivative of $\"\"$ .

\

Apply derivative on each side with respect to $\"\"$ .

\

$\"\"$

\

Chain rule of derivative: $\"\"$ .

\

Derivative of inverse cosine function : $\"\"$ .

\

$\"\"$

\

$\"\"$ .

\

$\"\"$

\

$\"\"$

\

The domain of the function $\"\"$ :

\

Domain of cosine function is $\"\"$ .

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

The domain of the function $\"\"$ is $\"\"$ .

\

Consider $\"\"$ .

\

The domain of the function is $\"\"$ .

\

$\"\"$

\

The domain of the function $\"\"$ is $\"\"$ .

\

$\"\"$

\

The domain of the function $\"\"$ is $\"\"$ .

\

The domain of the function $\"\"$ is $\"\"$ .