The function is
.
Definite integral as area of the region:
\If
is continuous and non-negative on the closed interval
, then the area of the region bounded by the graph
, the
-axis and the vertical lines
and
, then area
.
Observe the graph:
\In this case
,
to
.
The area of the region bounded by the graph
, the
-axis and the vertical lines
and ,
, then area
.
.