(a)
\The curve equation is
, lines are
,
and
and the region is rotated about
-axis.
Method of Cylinders :
\The volume of the solid obtained by rotating about
-axis, the region of the curve
from
to
is
.
Set up the integral for the volume using above formula.
\Here
,
and
.
Find the volume obtained by rotating region about
-axis, bounded by the curve
and
from
to
is
.
Use calculator to find
.
Therefore the reslt is
.
(a)
.
(b)
.