Definition:Non-symmetric Relation
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Definition
Let $\mathcal R \subseteq S \times S$ be a relation in $S$.
$\mathcal R$ is non-symmetric iff it is neither symmetric nor asymmetric.
Example
An example of a non-symmetric relation:
Let $S = \left\{{a, b, c}\right\}, \mathcal R = \left\{{\left({a, b}\right), \left({b, a}\right), \left({a, c}\right)}\right\}$.
- $\mathcal R$ is not symmetric, because $\left({a, c}\right) \in \mathcal R$ but $\left({c, a}\right) \notin \mathcal R$.
- $\mathcal R$ is not asymmetric, because $\left({a, b}\right) \in \mathcal R$ and $\left({b, a}\right) \in \mathcal R$.
Also see
- Results about symmetry of relations can be found here.