p q p^q r ~r (p^q) -> ~r
--- --- ------- --- --- -------------
T T T T F F
T T T F T T
T F F T F T
T F F F T T
F T F T F T
F T F F T T
F F F T F T
F F F F T T
An implication is false ONLY in the case where the antecedent is true but the consequent is nonetheless false.
John
Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it