Set Operations

Tom Kelliher, MA 190

Feb. 18, 2008

$A \cup \emptyset = A$ Identity laws
$A \cap U = A$  
$A \cup U = U$ Domination laws
$A \cap \emptyset = \emptyset$  
$A \cup A = A$ Idempotent laws
$A \cap A = A$  
   
$\overline{(\overline{A})} = A$ Complementation law
$A \cup B = B \cup A$ Commutative laws
$A \cap B = B \cap A$  
$(A \cup B) \cup C \equiv A \cup (B \cup C)$ Associative laws
$(A \cap B) \cap C \equiv A \cap (B \cap C)$  
$A \cap (B \cup C) = (A \cap B) \cup (A \cap C)$ Distributive laws
$A \cup (B \cap C) = (A \cup B) \cap (A \cup C)$  
   
$\overline{A \cap B} = \overline{A} \cup \overline{B}$ De Morgan's laws
$\overline{A \cup B} = \overline{A} \cap \overline{B}$  
$A \cup (A \cap B) = A$ Absorption laws
$A \cap (A \cup B) = A$  
   
$A \cup \overline{A} = U$ Complement laws
$A \cap \overline{A} = \emptyset$  

Exercises

Pg. 120: 7; 17; 19; 23.
Pg. 131: 16 c, d; 19, 45.

Thomas P. Kelliher 2008-02-18
Tom Kelliher