# De Morgan's laws

In boolean algebra, DeMorgan's laws are the laws of how a NOT Gate effects AND and OR statements:

$\overline{A \cdot B} = \overline {A} + \overline {B}$
$\overline{A + B} = \overline {A} \cdot \overline {B}$

[1] They can be remembered by "break the line, change the sign".

## Truth tables

The following truth tables prove DeMorgan's laws.

 INPUT OUTPUT 1 OUTPUT 2 A B NOT (A AND B) (NOT A) OR (NOT B) 0 0 1 1 0 1 1 1 1 0 1 1 1 1 0 0
 INPUT OUTPUT 1 OUTPUT 2 A B NOT (A OR B) (NOT A) AND (NOT B) 0 0 1 1 0 1 0 0 1 0 0 0 1 1 0 0