$\"\"$

Gradient of the function :

$\"\"$ .

The gradient of the vector is normal to the level surfaces.

$\"\"$

The equation is $\"\"$ and the point is $\"\"$ .

Rewrite the equation as $\"\"$ .

Consider $\"\"$ .

Find gradient of the function.

$\"\"$ .

Substitute the point $\"\"$ in above equation.

$\"\"$

Find the unit vector.

$\"\"$

Unit normal vector is $\"\"$ . $\"\"$

Unit normal vector is $\"\"$ .