Absolute value

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The absolute value is sometimes called "abs"


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.


More strictly the function should be given as: [math]|\cdot|:\mathbb{R}\rightarrow\mathbb{R}_{\ge 0}[/math]


  1. [math]|-2|=2[/math]
  2. [math]|2|=2[/math]
  3. [math]|0|=0[/math]