Inverse of Central Unit of Ring is in Center

Theorem
Let $R$ be a ring.

Let $\map Z R$ denote the center of $R$.

Let $u \in R$ be a unit of $R$.

Then:
 * $u \in \map Z R \implies u^{-1} \in \map Z R$

Proof
Follows directly from the definition of center and Inverse of Unit in Centralizer of Ring is in Centralizer.