Difference between revisions of "Absolute value"
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The absolute value is sometimes called "abs" | The absolute value is sometimes called "abs" | ||
Latest revision as of 18:15, 18 March 2016
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The absolute value is sometimes called "abs"
Definition
The absolute value is a function [math]|\cdot|:\mathbb{R}\rightarrow\mathbb{R}[/math] given by:
[math]|x|=\left\{\begin{array}{lr} x & x\ge 0\\ -x & \text{otherwise} \end{array}\right.[/math]
It simply returns the positive value of a number.
Note
More strictly the function should be given as: [math]|\cdot|:\mathbb{R}\rightarrow\mathbb{R}_{\ge 0}[/math]
Examples
- [math]|-2|=2[/math]
- [math]|2|=2[/math]
- [math]|0|=0[/math]
