Changes

The [[Complex_number|complex numbers]] <math>\mathbb{C}</math> are algebraically closed by the [[Fundamental_Theorem_of_Algebra|Fundamental Theorem of Algebra]], however the [[Rational_number|rational numbers]] <math>\mathbb{Q}</math> are not since x²+1 does not have a root. This same polynomial shows the [[Real_number|real numbers]] <math>\mathbb{R}</math> are also not algebraically closed, yielding as a [[Corollary|corollary]] (by the equivalence) that <math>\textrm{Aut}(\mathbb{R})</math> has [[Cardinality|cardinality]] the [[Continuum|continuum]].

The [[Complex_number|complex numbers]] <math>\mathbb{C}</math> are algebraically closed by the [[Fundamental_Theorem_of_Algebra|Fundamental Theorem of Algebra]], however the [[Rational_number|rational numbers]] <math>\mathbb{Q}</math> are not since x²+1 does not have a root. This same polynomial shows the [[Real_number|real numbers]] <math>\mathbb{R}</math> are also not algebraically closed, yielding as a [[Corollary|corollary]] (by the equivalence) that <math>\textrm{Aut}(\mathbb{R})</math> has [[Cardinality|cardinality]] the [[Continuum|continuum]].