Computer Systems

Cards (11)

  • Boolean algebra concerns representing values with letters and simplifying expressions
  • Boolean values
    TRUE and FALSE, which can be represented as 1 and 0 respectively
  • Boolean algebra notation
    • A, B, C, etc. (unknown Boolean values)
    • A (NOT A)
    • A • B (A AND B)
    • AB (alternative notation for A AND B)
    • A + B (A OR B)
  • Algebraic operations have an order of precedence, meaning that some operations must be applied before others
  • Order of precedence in Boolean algebra
    • Brackets
    • NOT
    • AND
    • OR
  • Boolean identities
    • A • 0 = 0
    • B • 1 = B
    • C • C = C
    • D + 0 = D
    • E + 1 = 1
    • F + F = F
    • G = G
  • De Morgan's laws
    "Break the bar and change the sign"
  • Applying De Morgan's laws

    1. Break the bar
    2. Change the sign
  • Distributive rules in Boolean algebra: A (B + C) = A B + A • C
  • Example 1: Simplify A + B • A
    • A + B • A
    = B + A
    = 1
  • Example 2: Simplify C • B + C • B
    • C • B + C • B
    = B • (C + C)
    = B