$\"\"$

The function is $\"\"$ .

Derivative on each side with respect to $\"\"$ .

$\"\"$

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

$\"\"$

The slope of the horizontal tangent is 0.

To determine the points, equate $\"\"$ .

$\"\"$

$\"\"$ is undefined.

So the function has no horizontal tangent line.

$\"\"$

The function has no horizontal tangent line.