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