\
Table of values of an increasing function
is given.
Determine the lower and upper estimates for
.
Lower estimate for increasing function is left end approximation of the function.
\Divide the interval
into
subintervals.
Number of subintervals are
.
Width of the interval is :
.
Left end points are
.
Lower estimation for
.

Substitute corresponding function values in above expression from the table.
\
Lower estimation for
is
.
Upper estimate for increasing function is right end approximation of the function.
\Right end points are
.
Upper estimation for
.

Substitute corresponding function values in above expression from the table.
\
.
Upper estimation for
is
.
\
Lower estimation for
is
.
Upper estimation for
is
.