Metamath Proof Explorer


Theorem swapf1val

Description: The object part of the swap functor. See also swapf1vala . (Contributed by Zhi Wang, 7-Oct-2025)

Ref Expression
Hypotheses swapfval.c ⊢ φ → C ∈ U
swapfval.d ⊢ φ → D ∈ V
swapf2fvala.s ⊢ S = C × c D
swapf2fvala.b ⊢ B = Base S
swapf1val.o No typesetting found for |- ( ph -> ( C swapF D ) = <. O , P >. ) with typecode |-
Assertion swapf1val ⊢ φ → O = x ∈ B ⟼ ⋃ x -1

Proof

Step Hyp Ref Expression
1 swapfval.c ⊢ φ → C ∈ U
2 swapfval.d ⊢ φ → D ∈ V
3 swapf2fvala.s ⊢ S = C × c D
4 swapf2fvala.b ⊢ B = Base S
5 swapf1val.o Could not format ( ph -> ( C swapF D ) = <. O , P >. ) : No typesetting found for |- ( ph -> ( C swapF D ) = <. O , P >. ) with typecode |-
6 5 fveq2d Could not format ( ph -> ( 1st ` ( C swapF D ) ) = ( 1st ` <. O , P >. ) ) : No typesetting found for |- ( ph -> ( 1st ` ( C swapF D ) ) = ( 1st ` <. O , P >. ) ) with typecode |-
7 1 2 3 4 swapf1vala Could not format ( ph -> ( 1st ` ( C swapF D ) ) = ( x e. B |-> U. `' { x } ) ) : No typesetting found for |- ( ph -> ( 1st ` ( C swapF D ) ) = ( x e. B |-> U. `' { x } ) ) with typecode |-
8 1 2 swapfelvv Could not format ( ph -> ( C swapF D ) e. ( _V X. _V ) ) : No typesetting found for |- ( ph -> ( C swapF D ) e. ( _V X. _V ) ) with typecode |-
9 5 8 eqeltrrd ⊢ φ → O P ∈ V × V
10 opelxp ⊢ O P ∈ V × V ↔ O ∈ V ∧ P ∈ V
11 10 biimpi ⊢ O P ∈ V × V → O ∈ V ∧ P ∈ V
12 op1stg ⊢ O ∈ V ∧ P ∈ V → 1 st ⁡ O P = O
13 9 11 12 3syl ⊢ φ → 1 st ⁡ O P = O
14 6 7 13 3eqtr3rd ⊢ φ → O = x ∈ B ⟼ ⋃ x -1