Propositional Logic · Tautologies

Lesson 1

Nikolai Chukhin · Alexander S. Kulikov

We say that formulas \(P\) and \(Q\) are equivalent, and write \(P \equiv Q\), if they define the same Boolean function.

  • Reformulating a mathematical statement can help to understand it better and eventually prove it.

  • Equivalent replacements in code make it more compact and readable. For example, instead of 
    if (x < 7 or y > 5) and (x < 7 or z == 12):
    ...
    it is better to write 
    if (x < 7) or (y > 5 and z == 12):
    ...