Observe the graph:
\The curve equation is
.
The distance from the center of the rectangle to the axis of revolution is
.
The height of the rectangle is
.
Shell method:
\Vertical axis of revolution.
\The volume of the solid is
.
The distance from the center of the rectangle to the axis of revolution is
.
The integral limits are
to
.
Substitute
,
,
and
in
.







.
.
.