Given two groups G , G â² {\displaystyle G,G'} , an isomorphism from G {\displaystyle G} to G â² {\displaystyle G'} is a function Ï : G â G â² {\displaystyle \phi :G\to G'\,} such that Ï {\displaystyle \phi } is a homomorphism and Ï {\displaystyle \phi } is bijective.
Two groups G , G â² {\displaystyle G,G'} are called isomorphic if an isomorphism from G {\displaystyle G} to G â² {\displaystyle G'} exists.
