Absorption Laws (Set Theory)/Intersection with Union

Theorem

 * $S \cap \left({S \cup T}\right) = S$

Comment
$S \cap \left ({S \cup T}\right)$ is also equal to $S \cup \left ({S \cap T}\right)$:

See Union with Intersection.

These two results together are known as the Absorption Laws, corresponding to the equivalent results in logic.