3 votes 3 votes Consider the compund propositions given below as: $p \vee \sim (p \wedge q)$ $(p \wedge \sim q) \vee \sim (p \wedge q)$ $p \wedge (q \vee r)$ Which of the above propositions are tautologies i and iii ii and iii i and ii i, ii, and iii Mathematical Logic ugcnetcse-dec2015-paper2 mathematical-logic + – go_editor asked Aug 8, 2016 • edited Jan 8 by makhdoom ghaya go_editor 2.5k views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
Best answer 7 votes 7 votes $p\vee (p\wedge q)`$ = p+p`+q` = 1+q`= 1 so tautology. C and b cant be tautology so no option is matching. Prashant. answered Aug 8, 2016 • selected Sep 1, 2016 by Tauhin Gangwar Prashant. comment Share Follow See all 2 Comments See all 2 2 Comments reply papesh commented Aug 8, 2016 reply Follow Share How b. Is tautology 0 votes 0 votes Prashant. commented Aug 8, 2016 reply Follow Share only a is tautology but since c nver be tautology so i choose b . 1 votes 1 votes Please log in or register to add a comment.
–1 votes –1 votes p∨~(p∧q) p∨~(p∧q) =p ∨ ~p v~q p ∨ ~p is always true a is a tautology (p∧~q)∨~(p∧q) (p∧~q)∨~(p∧q) = (p∧~q)∨(~pv~q) is also tautology p∧(q∨r) p∧(q∨r) = (p^q) v (p^r) is not a tautology Answer C a and b sh!va answered Aug 8, 2016 sh!va comment Share Follow See all 0 reply Please log in or register to add a comment.