# Absolute value

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The absolute value is sometimes called "abs"

## Definition

The absolute value is a function $|\cdot|:\mathbb{R}\rightarrow\mathbb{R}$ given by:

$|x|=\left\{\begin{array}{lr} x & x\ge 0\\ -x & \text{otherwise} \end{array}\right.$

It simply returns the positive value of a number.

### Note

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

## Examples

1. $|-2|=2$
2. $|2|=2$
3. $|0|=0$