$\"\"$

The function is $\"\"$ .

Apply first derivative with respect to $\"\"$ .

$\"\"$

Apply second derivative with respect to $\"\"$ .

$\"\"$

Determine the values of $\"\"$ at which $\"\"$ or $\"\"$ does not exist.

$\"\"$

Simplify the expression.

$\"\"$

$\"\"$ or $\"\"$

Solve for $\"\"$ .

$\"\"$

Solve for $\"\"$ .

$\"\"$

Here the values of $\"\"$ is in imaginary, so does not consider it.

The values of $\"\"$ are $\"\"$ and $\"\"$ . $\"\"$

Test for concavity in the intervals $\"\"$ , $\"\"$ and $\"\"$ .

\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \

$\"\"$

The function is concave downward in the intervals $\"\"$ and $\"\"$ .

The function is concave upward in the interval $\"\"$ .