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Viewing Version 2 of 'right hand rule'
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Title of object: right hand rule
Canonical Name: RightHandRule
Type: Definition

Created on: 2006-06-08 16:27:23
Modified on: 2006-06-08 16:44:08

Creator: Wkbj79
Modifier: Wkbj79
Author: Wkbj79

Classification: msc:26A42, msc:41-01

Preamble:

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Content:

The {\sl right hand rule\/} for computing the Riemann integral $\int_a^b f(x) \, dx$ is

$$\int_a^b f(x) \, dx = \lim_{n \to \infty} \sum_{j=1}^n f \left( a + \frac{(b-a)j}{n} \right) \left( \frac{b-a}{n} \right).$$

The Riemann integral can be approximated by using a definite value for $n$ rather than taking a limit.

If the Riemann integral is considered as a measure of area under a curve, then the expressions $f \left( a + \frac{(b-a)j}{n} \right)$ represent the heights of the rectangles, and $\frac{b-a}{n}$ is the common width of the rectangles.