Suppose that $ f(x) $ is continuously differentiable on the interval [a,b].

  • Let N be a positive integer
  • Let $ M = Max \{ |f'(x)| : a \leq x \leq b \} $
  • Let $ h = \frac{(b-a)}{N} $
  • Let $ R_N $ denote the "right endpoint"

Riemann Sum for the integral

$  I = \int_a^b f(x) dx . $

In other words,

$  R_N = \sum_{n=1}^N f(a + n h) h . $

Explain why the error, $ E = | R_N - I | $, satisfies

$  E \le \frac{M(b-a)^2}{N}.  $

(I moved all the discussion that used to be here to the discussion tab. I still think it would be nice to put a polished proof of the estimate here. --Bell 14:49, 14 October 2008 (UTC))

Alumni Liaison

Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett