The curve equations are
.
Shell method:
\The plane region is revolving about the
-axis.
The volume of the solid is
.
Observe the figure:
\On interval
:
The distance from the center of the rectangle to the axis of revolution is
.
The height of the rectangle is
.
On interval
:
The distance from the center of the rectangle to the axis of revolution is
.
The height of the rectangle is
.
Evaluate the integral
.
Apply formula:
.





.
.
.