Metamath Proof Explorer


Theorem ifpan123g

Description: Conjunction of conditional logical operators. (Contributed by RP, 18-Apr-2020)

Ref Expression
Assertion ifpan123g if-φχτif-ψθη¬φχφτ¬ψθψη

Proof

Step Hyp Ref Expression
1 dfifp4 if-φχτ¬φχφτ
2 dfifp4 if-ψθη¬ψθψη
3 1 2 anbi12i if-φχτif-ψθη¬φχφτ¬ψθψη