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