What exactly does tautology mean? - Mathematics Stack Exchange
Oct 17, 2016 · To simplify, a tautology in plain English is stating the same thing twice but in a different manner. So for example, the statement " this meaningless statement is non-meaningful " is a …
discrete mathematics - Show that (p ∧ q) → (p ∨ q) is a tautology ...
Mar 7, 2016 · I am having a little trouble understanding proofs without truth tables particularly when it comes to → Here is a problem I am confused with: Show that (p ∧ q) → (p ∨ q) is a tautology The firs...
logic - Tautology, Valid, Contingent, Unsatisfiable, Contradiction ...
Sep 8, 2019 · I am trying to clear my doubts about various terms: tautology, contradiction, contingent, satisifiable, unsatisfiable, valid and invalid. I have read on them from various sources, and am putting …
How do I prove that $[¬P ∧ (P ∨ Q)] → Q$ is tautology without using ...
2 Using a Fitch style proof, this tautology can be proved by contradiction. Assume the statement is false, show that this assumption entails a contradiction, then negate the assumption.
discrete mathematics - Is $ [p \land (p \to q)] \to q$ a tautology ...
Jan 14, 2016 · In order for a proposition to be a tautology, we need that the corresponding function always evaluates to 1, regardless of the input values. Now we will explain the building-block …
logic - Without constructing a truth table show that the statement ...
Aug 21, 2020 · Without constructing a truth table show that the statement formula ~ (~p→~q)→~ (q→p) is a tautology Ask Question Asked 5 years, 3 months ago Modified 5 years, 3 months ago
logic - How do I prove this statement is a tautology without using ...
Apr 13, 2020 · The easiest way to show that (0) is a tautology without using a truth table or Karnough map, is with a proof tree. To use this method, we will first assume that (0) is false, and derive a …
logic - Given the premises p→q and ¬p→¬q, prove that p is logically ...
Jan 19, 2020 · It is a tautology in this particular case because the premises are known to be true. p↔q is not a tautology in general.
I can't seem to prove that (p ∨ q) ∧ (¬p ∨ r) → (q ∨ r) is a tautology.
Feb 7, 2021 · I'm stuck on this last step. The only law that seemed hopeful was the distribution law but that won't even work here. I resorted to using a truth table to prove this but I really want to know if it's …
Use induction to prove that it can be determined whether or not the ...
Jan 10, 2025 · Use induction to prove that it can be determined whether or not the disjunction $A_1\lor\cdots\lor A_n$ is a tautology. Ask Question Asked 10 months ago Modified 10 months ago