Metamath Proof Explorer


Theorem parhomideq2

Description: Variant of parhomideq . (Contributed by Zhi Wang, 14-Sep-2026) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Hypotheses parhomval.h
|- H = ( x e. B , y e. B |-> if ( x = y , { J } , if ( ( x = X /\ y = Y ) , S , (/) ) ) )
parhomideq.f
|- ( ph -> F e. ( U H V ) )
parhomideq.e
|- ( ph -> U = V )
parhomideq2.s
|- S e. _V
parhomideq2.j
|- J e. _V
parhomideq2.u
|- ( ph -> U e. B )
parhomideq2.v
|- ( ph -> V e. B )
Assertion parhomideq2
|- ( ph -> F = J )

Proof

Step Hyp Ref Expression
1 parhomval.h
 |-  H = ( x e. B , y e. B |-> if ( x = y , { J } , if ( ( x = X /\ y = Y ) , S , (/) ) ) )
2 parhomideq.f
 |-  ( ph -> F e. ( U H V ) )
3 parhomideq.e
 |-  ( ph -> U = V )
4 parhomideq2.s
 |-  S e. _V
5 parhomideq2.j
 |-  J e. _V
6 parhomideq2.u
 |-  ( ph -> U e. B )
7 parhomideq2.v
 |-  ( ph -> V e. B )
8 1 4 parhomval
 |-  ( ( U e. B /\ V e. B ) -> ( U H V ) = if ( U = V , { J } , if ( ( U = X /\ V = Y ) , S , (/) ) ) )
9 6 7 8 syl2anc
 |-  ( ph -> ( U H V ) = if ( U = V , { J } , if ( ( U = X /\ V = Y ) , S , (/) ) ) )
10 3 iftrued
 |-  ( ph -> if ( U = V , { J } , if ( ( U = X /\ V = Y ) , S , (/) ) ) = { J } )
11 9 10 eqtrd
 |-  ( ph -> ( U H V ) = { J } )
12 2 11 eleqtrd
 |-  ( ph -> F e. { J } )
13 12 elsnd
 |-  ( ph -> F = J )