\

\

The function is

\"\"

.

\

Apply derivative on each side with respect to

\"\"

.

\

\"\"

\

\

\

\

\

The sign changes of $\"\"$ :

\

$\"\"$ on $\"\"$ .

\

$\"\"$ on $\"\"$ .

\

$\"\"$ on $\"\"$ .

\

$\"\"$

\

$\"\"$ on $\"\"$ .

\

So $\"\"$ on $\"\"$ .

\

Therefore $\"\"$ .

\

\

\

\

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$\"\"$ .