Metamath Proof Explorer


Theorem swapf1a

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

Ref Expression
Hypotheses swapf1a.o No typesetting found for |- ( ph -> ( C swapF D ) = <. O , P >. ) with typecode |-
swapf1a.s ⊢ S = C × c D
swapf1a.b ⊢ B = Base S
swapf1a.x ⊢ φ → X ∈ B
Assertion swapf1a ⊢ φ → O ⁡ X = 2 nd ⁡ X 1 st ⁡ X

Proof

Step Hyp Ref Expression
1 swapf1a.o Could not format ( ph -> ( C swapF D ) = <. O , P >. ) : No typesetting found for |- ( ph -> ( C swapF D ) = <. O , P >. ) with typecode |-
2 swapf1a.s ⊢ S = C × c D
3 swapf1a.b ⊢ B = Base S
4 swapf1a.x ⊢ φ → X ∈ B
5 2 3 4 elxpcbasex1 ⊢ φ → C ∈ V
6 2 3 4 elxpcbasex2 ⊢ φ → D ∈ V
7 5 6 2 3 1 swapf1val ⊢ φ → O = x ∈ B ⟼ ⋃ x -1
8 simpr ⊢ φ ∧ x = X → x = X
9 8 sneqd ⊢ φ ∧ x = X → x = X
10 9 cnveqd ⊢ φ ∧ x = X → x -1 = X -1
11 10 unieqd ⊢ φ ∧ x = X → ⋃ x -1 = ⋃ X -1
12 eqid ⊢ Base C = Base C
13 eqid ⊢ Base D = Base D
14 2 12 13 xpcbas ⊢ Base C × Base D = Base S
15 3 14 eqtr4i ⊢ B = Base C × Base D
16 4 15 eleqtrdi ⊢ φ → X ∈ Base C × Base D
17 2nd1st ⊢ X ∈ Base C × Base D → ⋃ X -1 = 2 nd ⁡ X 1 st ⁡ X
18 16 17 syl ⊢ φ → ⋃ X -1 = 2 nd ⁡ X 1 st ⁡ X
19 18 adantr ⊢ φ ∧ x = X → ⋃ X -1 = 2 nd ⁡ X 1 st ⁡ X
20 11 19 eqtrd ⊢ φ ∧ x = X → ⋃ x -1 = 2 nd ⁡ X 1 st ⁡ X
21 opex ⊢ 2 nd ⁡ X 1 st ⁡ X ∈ V
22 21 a1i ⊢ φ → 2 nd ⁡ X 1 st ⁡ X ∈ V
23 7 20 4 22 fvmptd ⊢ φ → O ⁡ X = 2 nd ⁡ X 1 st ⁡ X