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๐Ÿง  Truth Tables

๐Ÿง  Truth Tables

Truth tables are used to represent the output of logical expressions for all possible input combinations. Each row corresponds to a unique input state, and the columns show the resulting output.


๐Ÿ”ค Notation Legend

SymbolMeaning
ยฌANOT A (negation)
A โˆง BA AND B (conjunction)
A โˆจ BA OR B (disjunction)
A โŠ• BA XOR B (exclusive OR)
A โ†’ BA IMPLIES B
A โ†” BA IFF B (biconditional)

โœ… Basic Truth Tables

1๏ธโƒฃ NOT (Negation)

AยฌA
01
10

2๏ธโƒฃ AND (Conjunction)

ABA โˆง B
000
010
100
111

3๏ธโƒฃ OR (Disjunction)

ABA โˆจ B
000
011
101
111

4๏ธโƒฃ XOR (Exclusive OR)

ABA โŠ• B
000
011
101
110

๐Ÿ” Compound Expressions

Example: (A โˆง B) โˆจ ยฌC

ABCA โˆง BยฌC(A โˆง B) โˆจ ยฌC
000011
001000
010011
011000
100011
101000
110111
111101

๐Ÿงฉ Tips for Building Truth Tables

  • List all input combinations using binary counting.
  • Compute intermediate columns for sub-expressions.
  • Use consistent notation and spacing for clarity.
  • Highlight final output column for emphasis.

Check: ๐Ÿ“Š Baseโ€‘b Recursive Listing Method


๐Ÿงฎ Expandable Framework

To add more operators or multi-bit logic, duplicate the table structure and extend with additional columns. For example:

  • NAND: ยฌ(A โˆง B)
  • NOR: ยฌ(A โˆจ B)
  • XNOR: ยฌ(A โŠ• B)
  • Majority: (A โˆง B) โˆจ (A โˆง C) โˆจ (B โˆง C)

๐Ÿง  Set-Theoretic Analogy (Optional)

  • A โˆง B โ†’ Intersection: $ A \cap B $
  • A โˆจ B โ†’ Union: $ A \cup B $
  • ยฌA โ†’ Complement: $ A^c $
  • A โŠ• B โ†’ Symmetric Difference: $ A \triangle B $

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