**Description:** Simplification of conjunction. (Contributed by NM, 9-Mar-2012)

Ref | Expression | ||
---|---|---|---|

Assertion | simp3ll | $${\u22a2}\left({\theta}\wedge {\tau}\wedge \left(\left({\phi}\wedge {\psi}\right)\wedge {\chi}\right)\right)\to {\phi}$$ |

Step | Hyp | Ref | Expression |
---|---|---|---|

1 | simpll | $${\u22a2}\left(\left({\phi}\wedge {\psi}\right)\wedge {\chi}\right)\to {\phi}$$ | |

2 | 1 | 3ad2ant3 | $${\u22a2}\left({\theta}\wedge {\tau}\wedge \left(\left({\phi}\wedge {\psi}\right)\wedge {\chi}\right)\right)\to {\phi}$$ |