Exercise logic.propositional.dnf
Description
Proposition to DNF
Derivation
![](http://ideas.cs.uu.nl/images/external.png)
(T /\ ~((q -> r) || (q -> r))) || q || r
⇒ logic.propositional.defimpl(T /\ ~(~q || r || (q -> r))) || q || r
⇒ logic.propositional.defimpl(T /\ ~(~q || r || ~q || r)) || q || r
⇒ logic.propositional.idempor(T /\ ~(~q || r)) || q || r