$\"\"$

The function is $\"\"$ and the interval is $\"\"$ .

Find the area of the surface formed by revolving the about $\"\"$ -axis.

Surface area is $\"\"$ .

$\"\"$ .

Differentiate on each side.

$\"\"$

$\"\"$ .

Substitute $\"\"$ and $\"\"$ in $\"\"$ .

$\"\"$

$\"\"$ .

$\"\"$

Surface area is $\"\"$ .