Introduction

In working with logic relations in digital form, we need a set of rules for symbolic manipulation which will enable us to simplify complex expressions and solve for unknowns. Originally, Boolean algebra which was formulated by George Boole, an English mathematician (1815-1864) described propositions whose outcome would be either true or false. In computer work it is used in addition to describe circuits whose state can be either 1 (true) or 0 (false).Using the relations defined in the AND, OR and NOT operation, a number of postulates are stated in Table 2.1 [Ref.3].

• P1 : X = 0 or X = 1
• P2 : 0 0 = 0
• P3 : 1 + 1 = 1
• P4 : 0 + 0 = 0
• P5 : 1 1 = 1
• P6 : 1 0 = 0 1 = 0
• P7 : 1 + 0 = 0 + 1 = 1

Table 2.1 Boolean Postulates