$\"\"$

\

Consider $\"\"$ is an even function.

\

From the definition of even function : $\"\"$

\

The composite function is $\"\"$ .

\

$\"\"$

\

$\"\"$ ( Since $\"\"$ )

\

$\"\"$

\

$\"\"$ .

\

So $\"\"$ is an even function.

\

$\"\"$

\

$\"\"$ is also an even function.