Metamath Proof Explorer


Theorem ifpan23

Description: Conjunction of conditional logical operators. (Contributed by RP, 20-Apr-2020)

Ref Expression
Assertion ifpan23
|- ( ( if- ( ph , ps , ch ) /\ if- ( ph , th , ta ) ) <-> if- ( ph , ( ps /\ th ) , ( ch /\ ta ) ) )

Proof

Step Hyp Ref Expression
1 ifpan123g
 |-  ( ( if- ( ph , ps , ch ) /\ if- ( ph , th , ta ) ) <-> ( ( ( -. ph \/ ps ) /\ ( ph \/ ch ) ) /\ ( ( -. ph \/ th ) /\ ( ph \/ ta ) ) ) )
2 an4
 |-  ( ( ( ( -. ph \/ ps ) /\ ( ph \/ ch ) ) /\ ( ( -. ph \/ th ) /\ ( ph \/ ta ) ) ) <-> ( ( ( -. ph \/ ps ) /\ ( -. ph \/ th ) ) /\ ( ( ph \/ ch ) /\ ( ph \/ ta ) ) ) )
3 dfifp4
 |-  ( if- ( ph , ( ps /\ th ) , ( ch /\ ta ) ) <-> ( ( -. ph \/ ( ps /\ th ) ) /\ ( ph \/ ( ch /\ ta ) ) ) )
4 ordi
 |-  ( ( -. ph \/ ( ps /\ th ) ) <-> ( ( -. ph \/ ps ) /\ ( -. ph \/ th ) ) )
5 ordi
 |-  ( ( ph \/ ( ch /\ ta ) ) <-> ( ( ph \/ ch ) /\ ( ph \/ ta ) ) )
6 4 5 anbi12i
 |-  ( ( ( -. ph \/ ( ps /\ th ) ) /\ ( ph \/ ( ch /\ ta ) ) ) <-> ( ( ( -. ph \/ ps ) /\ ( -. ph \/ th ) ) /\ ( ( ph \/ ch ) /\ ( ph \/ ta ) ) ) )
7 3 6 bitr2i
 |-  ( ( ( ( -. ph \/ ps ) /\ ( -. ph \/ th ) ) /\ ( ( ph \/ ch ) /\ ( ph \/ ta ) ) ) <-> if- ( ph , ( ps /\ th ) , ( ch /\ ta ) ) )
8 1 2 7 3bitri
 |-  ( ( if- ( ph , ps , ch ) /\ if- ( ph , th , ta ) ) <-> if- ( ph , ( ps /\ th ) , ( ch /\ ta ) ) )