Category:Definitions/Extended Real Numbers

From ProofWiki
Jump to navigation Jump to search

This category contains definitions related to Extended Real Numbers.
Related results can be found in Category:Extended Real Numbers.


The extended real number line $\overline \R$ is defined as:

$\overline \R := \R \cup \set {+\infty, -\infty}$

that is, the set of real numbers together with two auxiliary symbols:

$+\infty$, positive infinity
$-\infty$, negative infinity

such that:

$\forall x \in \R: x < +\infty$
$\forall x \in \R: -\infty < x$