We can find truth value of S = (P Ú Ø (Q Ú R)) Ù (Q Ú Ø (P)) from truth values of P, Q, and R, parse tree, and truth table.
| P(x) | Q(x) | Ø P(x) | P(x)Ù Q(x) | P(x)Ú Q(x) |
| True | True | False | True | True |
| True | False | False | False | True |
| False | True | True | False | True |
| False | False | True | False | False |