Metamath Proof Explorer


Theorem anandir

Description: Distribution of conjunction over conjunction. (Contributed by NM, 24-Aug-1995)

Ref Expression
Assertion anandir φψχφχψχ

Proof

Step Hyp Ref Expression
1 anidm χχχ
2 1 anbi2i φψχχφψχ
3 an4 φψχχφχψχ
4 2 3 bitr3i φψχφχψχ