\"\"

\

The limit function is \"\".

\

Let \"\" and \"\".

\

Therefore, \"\".

\

As \"\", \"\" approaches to \"\".

\

\"\"

\

\"\"

\

The above limit is in indeterminate form \"\", hence apply L\"\"Hospital\"\"s rule.

\

\"\"

\

\"\"

\

\"\"

\

\"\".

\

\"\"

\

\"\".