improve this answer answered Mar 29 at 9:22 user8268 7,306 1 4 12 feedback up vote 1 down vote We can define conjugacy as a group action on $G$. Formally, for any $g \in G$, we define $(g,x)=gxg^{-1}$ for all $x \in G$. The Orbit-Stabilizer Theorem gives a description of $|x^G|$ in