Question

Prove that (p ∨q)∧(~P∧q~) is a contradiction.

Answer 1

| p | q | p∨q | NP | Nq | NP∧ Nq | (Pq)∧(NpN∧q) |
| T | T | T | F | F | F | F |
| T | F | T | F | F | F | F |
| F | T | T | T | F | F | F |
| F | F | F | T | T | T | F |

∴ (P∨ q) ∧ (Np ∧ Nq) is a contradiction.