R*

In mathematics, the hyperreal numbers are the elements of one of several possible field extensions ∗ R {\displaystyle \ast \mathbb {R} } of the field of real numbers R {\displaystyle \mathbb {R} } , extensions that include certain classes of infinite and infinitesimal numbers. A hyperreal number x {\displaystyle x} is said to be finite when | x | < n {\displaystyle {|x|}