DEVELOPMENT OF BOOLEAN ALGEBRA

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Mathematician George Boole invented a new kind of algebra, the algebra of logic in the year 1854 popularly known as Boolean Algebra or Switching Algebra. He stated that symbols can be used to represent the structure of logical thought. Boolean algebra differs significantly from conventional algebra. This algebra deals with the rules by which the logical operations are carried out. here, a digital circuit is represented by a set of input and output symbols and the circuit functions expressed as a set of Boolean relationships between this symbols.
           Boolean expressions are basically defined by stating that (i) a constant is a Boolean expression and (ii) a variable is a Boolean expression. For example, if A is a Boolean expression, so is A bar. The combination of variables such as A bar B and A bar B+C are also Boolean expressions. However, A-B is not a Boolean expression.

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