The function is
and the interval is
.
Area of the function is
.
Where
and
.
Let number of subintervals be
.

Substitute
in
.
.



Apply formula
.

Apply summation formula
.
Apply summation formula
.




As
, then
.


Area of the region is between
and
-axis is
sq-units.
Graph :
\Graph the region :
\Area of the region is
sq-units.
Area of the region is
sq-units.