The function
is a linear function.
Consider
on interval
.
The definite integral is
.
Describe the size of error when the Trapezoidal Rule is used to approximate
.
If
has a continuous second derivative on
, then the error approximating the integral
by Trapezoidal Rule is
,
.
The definite integral is
.

Apply derivative on each side with respect to
.


.
The error approximating the integral is
.
In this case
and
.

.
The size of error is zero because the Trapezoidal Rule always perfectly fit under a linear function.
\Graph the function:
on
.
Observe the graph:
\The Trapezoidal Rule perfectly fits a linear function.
\The size of error is zero because the Trapezoidal Rule always perfectly fit under a linear function.
\Graph of the function:
on
.
.