a) The rectangles in the graph below illustrate a
Riemann sum for
on the interval .
The value of this Riemann sum
is
,
and this Riemann sum is an
the area of the region enclosed by , the xaxis,
and the vertical lines x = 3 and x = 7.

Left endpoint Riemann sum for on

b) The rectangles in the graph below illustrate a
Riemann sum
for on the interval
.
The value of this Riemann sum is
,
and this Riemann sum is an
the area of the region enclosed by ,
the xaxis, and the vertical lines x = 3 and x = 7.

Right endpoint Riemann sum for on
