Set Complement/Examples/Positive Real Numbers in Real Numbers

Example of Set Complement
Let the universe $\Bbb U$ be defined to be the set of real numbers $\R$.

Let the set of (strictly) positive real numbers be denoted by $\R_{>0}$.

Then:
 * $\relcomp {} {\R_{>0} } = \R_{\le 0}$

the set of non-negative real numbers.