The equations of the curves are
and
.
Moments and center of mass of a planar lamina:
\Let
and
be continuous functions such that
on
, and consider the planar lamina of uniform density
bounded by the graphs of
and
.
The moments about the
-axis and
-axis are
.
.
The center of mass
is
and
, where
is the mass of the lamina.
Graph :
\Graph the curves
and
.
.gif\")
Observe the graph:
\The curves intersects on
.
Consider
and
.
on
.
Find
.
Substitute
,
and
in
.








.
Find
.
Since the center of mass lies on the axis of symmetry,
.
Find the center of mass
.
The center of mass
is
and
, where
is the mass of the lamina.
Substitute
,
and
in
.







.
Substitute
and
in
.

.
Substitute
and
in
.

.
The center of mass
.
,
and
.