Question

Assume the following hypotheses (1) "If it does not rain or if it is not foggy, then the sailing race will be held and the lifesaving demonstration will go on," (2) "If the sailing race is held, then the trophy will be awarded," and (3) "The trophy was not awarded." Using rules of inference, show that these hypotheses imply the conclusion "It rained. 3.

Answer 1

aiven that Cons i des γ as the poo Pos ition '' It rains," hen ake take s be the Pso Rosiion " the sai ling sace oill be held Ke fas Psoos itn is fo → take be propos ition life saving demonsha'han uJillg on ake t be Pasposithion The tsephy ill be auasded" -Here we have given pren\i ses)-Ihfj (snl s→t, and t whese we oant to Concluse then oeset ug the oof in keep a note that is Vahd to eglate Sub ex pses othes eェprey )on) logially egui valent to thavn Giuen table explana uen belas

2 Reason Hy pothesis Hypothesis 2.1 s→t Modus tolen using one and tuoo 3 5 De Mo agan's lau and double 1. |﹁sv 기 | Addition using (twee) and (Seven