Bounded Above Subset of Real Numbers/Examples/Closed Interval from Minus Infinity to 2

Example of Bounded Above Subset of Real Numbers
The subset $S$ of the real numbers $\R$ defined as:
 * $S = \hointl {-\infty} 2$

is bounded above.

The set of all upper bounds of $S$ is:
 * $\closedint 2 \infty$