【正确答案】(1)用等值演算法:
(P→(P∧Q))∨R=(¬P∨(P∧Q))∨R=((¬P∨P)∧(¬P∨Q))∨R=¬P∨Q∨R.
当P,Q,R的指派分别取不同真假值时,此公式的结果有时为真,有时为假,故是可满足式.
(2)真值表法:
真值表中结果有真有假,故是可满足式.
| P | Q | R | P∧Q | P→(P∧Q) | (P→(P∧Q))V R |
| F | F | F | F | T | T |
| F | F | T | F | T | T |
| F | T | F | F | T | T |
| F | T | T | F | T | T |
| T | F | F | F | F | F |
| T | F | T | F | F | rr |
| T | T | F | T | T | T |
| T | T | T | T | T | T |