Metamath Proof Explorer


Theorem f1oprg

Description: An unordered pair of ordered pairs with different elements is a one-to-one onto function, analogous to f1oprswap . (Contributed by Alexander van der Vekens, 14-Aug-2017)

Ref Expression
Assertion f1oprg ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y → A ≠ C ∧ B ≠ D → A B C D : A C ⟶ 1-1 onto B D

Proof

Step Hyp Ref Expression
1 f1osng ⊢ A ∈ V ∧ B ∈ W → A B : A ⟶ 1-1 onto B
2 1 ad2antrr ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → A B : A ⟶ 1-1 onto B
3 f1osng ⊢ C ∈ X ∧ D ∈ Y → C D : C ⟶ 1-1 onto D
4 3 ad2antlr ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → C D : C ⟶ 1-1 onto D
5 disjsn2 ⊢ A ≠ C → A ∩ C = ∅
6 5 ad2antrl ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → A ∩ C = ∅
7 disjsn2 ⊢ B ≠ D → B ∩ D = ∅
8 7 ad2antll ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → B ∩ D = ∅
9 f1oun ⊢ A B : A ⟶ 1-1 onto B ∧ C D : C ⟶ 1-1 onto D ∧ A ∩ C = ∅ ∧ B ∩ D = ∅ → A B ∪ C D : A ∪ C ⟶ 1-1 onto B ∪ D
10 2 4 6 8 9 syl22anc ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → A B ∪ C D : A ∪ C ⟶ 1-1 onto B ∪ D
11 df-pr ⊢ A B C D = A B ∪ C D
12 11 eqcomi ⊢ A B ∪ C D = A B C D
13 12 a1i ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → A B ∪ C D = A B C D
14 df-pr ⊢ A C = A ∪ C
15 14 eqcomi ⊢ A ∪ C = A C
16 15 a1i ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → A ∪ C = A C
17 df-pr ⊢ B D = B ∪ D
18 17 eqcomi ⊢ B ∪ D = B D
19 18 a1i ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → B ∪ D = B D
20 13 16 19 f1oeq123d ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → A B ∪ C D : A ∪ C ⟶ 1-1 onto B ∪ D ↔ A B C D : A C ⟶ 1-1 onto B D
21 10 20 mpbid ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y ∧ A ≠ C ∧ B ≠ D → A B C D : A C ⟶ 1-1 onto B D
22 21 ex ⊢ A ∈ V ∧ B ∈ W ∧ C ∈ X ∧ D ∈ Y → A ≠ C ∧ B ≠ D → A B C D : A C ⟶ 1-1 onto B D