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I have a propositional formula that I have to convert to CNF and then write that in abreviated clausal form. I feel like i'm making a mistake somewhere but struggling to figure it out. Any idea what I am doing wrong here/what i'm missing?

my attempt: https://i.stack.imgur.com/0WsHf.jpg

Mauro ALLEGRANZA
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user2094257
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  • You are dropping brackets all over the place. Keep them up until you don't need them. – Graham Kemp Jun 19 '18 at 12:14
  • You are reading $((p \land q) \lor r) \to (p \to (q \land r)) \to \lnot q$ as $\Big(((p \land q) \lor r) \to (p \to (q \land r))\Big) \to \lnot q$ rather than the usual reading of $((p \land q) \lor r) \to \Big((p \to (q \land r)) \to \lnot q\Big)$. Are you sure that was what was intended? – Graham Kemp Jun 19 '18 at 12:26
  • @Graham Kemp I think I understood it in the second way. Might have added parenthesis in the wrong place... – user2094257 Jun 19 '18 at 12:30
  • Then it might be best to start over from the beginning, and take more care. – Graham Kemp Jun 19 '18 at 12:40

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$(q\vee r\vee\neg q)$ is a tautology, as is $(q\vee\neg r\vee\neg q)$. Neither is equivalent to $r$.

There also seem to be a few more errors due to dropped parenthesis, and I'm not sure you're reading the nested implication correctly. $A\to B\to C$ is normally understood as $A\to(B \to C)$.

Graham Kemp
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