proving an inequality

• Mar 4th 2013, 06:07 PM
xixi
proving an inequality
Let G be a non-abelian finite group, Z(G) be the center of G and $C_{G}(x)$ be the centralizer of the element x in G. Let $x \in G \setminus Z(G)$, so we have $|G| \geq 2|C_{G}(x)|$. Now how can I prove that $|G \setminus C_{G}(x)|>(|G|-|Z(G)|)/2$ ?
• Mar 7th 2013, 07:02 PM
johng
Re: proving an inequality
I assume that \ means set minus. Your problem really has nothing to do with centralizers and the center. Here's a solution.

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