Set Difference/Examples

Definition
Let $S$ and $T$ be sets such that:


 * $S = \left\{{1, 2, 3}\right\}$
 * $T = \left\{{2, 3, 4}\right\}$

Let $\setminus$ denote set difference.

Then:
 * $S \setminus T = \left\{{1}\right\}$

while:
 * $T \setminus S = \left\{{4}\right\}$

It can immediately be seen that $S \setminus T$ is not commutative.

Also see

 * Set Difference is Anticommutative