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. $$|0|=0$$