$\textbf{Subgroup}$
Let $(G,\cdot )$ be a group and $H\subset G$ a nonempty subset. $H$ is called a subgroup of $G$ if for all $a,b \in H$ the result $a\cdot b\in H$ and $a^{-1}\in H$.
Note: A subgroup is a group itself.
$\textbf{Subgroup}$
Let $(G,\cdot )$ be a group and $H\subset G$ a nonempty subset. $H$ is called a subgroup of $G$ if for all $a,b \in H$ the result $a\cdot b\in H$ and $a^{-1}\in H$.
Note: A subgroup is a group itself.
copied
๐๐ฎ๐๐ ๐ซ๐จ๐ฎ๐ฉ
Let (๐บ,โ ) be a group and ๐ปโ๐บ a nonempty subset. ๐ป is called a subgroup of ๐บ if for all ๐,๐โ๐ป the result ๐โ ๐โ๐ป and ๐โปยนโ๐ป.
Note: A subgroup is a group itself.