Theorem 3anor

Triple conjunction expressed in terms of triple disjunction. (Contributed by Jeff Hankins, 15-Aug-2009.) (Proof shortened by Wolf Lammen, 8-Apr-2022.)

Conclusion

\( \vdash \varphi \wedge \psi \wedge \chi \leftrightarrow \neg (\neg \varphi \vee \neg \psi \vee \neg \chi) \)

Proof

3ianor

con1bii _

bicomi _