Metamath Proof Explorer


Theorem br1cosscnvxrn

Description: A and B are cosets by the converse range Cartesian product: a binary relation. (Contributed by Peter Mazsa, 19-Apr-2020) (Revised by Peter Mazsa, 21-Sep-2021)

Ref Expression
Assertion br1cosscnvxrn ( ( 𝐴𝑉𝐵𝑊 ) → ( 𝐴 ( 𝑅𝑆 ) 𝐵 ↔ ( 𝐴 𝑅 𝐵𝐴 𝑆 𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 ecxrn ( 𝐴𝑉 → [ 𝐴 ] ( 𝑅𝑆 ) = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝐴 𝑅 𝑥𝐴 𝑆 𝑦 ) } )
2 ecxrn ( 𝐵𝑊 → [ 𝐵 ] ( 𝑅𝑆 ) = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝐵 𝑅 𝑥𝐵 𝑆 𝑦 ) } )
3 1 2 ineqan12d ( ( 𝐴𝑉𝐵𝑊 ) → ( [ 𝐴 ] ( 𝑅𝑆 ) ∩ [ 𝐵 ] ( 𝑅𝑆 ) ) = ( { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝐴 𝑅 𝑥𝐴 𝑆 𝑦 ) } ∩ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝐵 𝑅 𝑥𝐵 𝑆 𝑦 ) } ) )
4 inopab ( { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝐴 𝑅 𝑥𝐴 𝑆 𝑦 ) } ∩ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝐵 𝑅 𝑥𝐵 𝑆 𝑦 ) } ) = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐴 𝑆 𝑦 ) ∧ ( 𝐵 𝑅 𝑥𝐵 𝑆 𝑦 ) ) }
5 3 4 eqtrdi ( ( 𝐴𝑉𝐵𝑊 ) → ( [ 𝐴 ] ( 𝑅𝑆 ) ∩ [ 𝐵 ] ( 𝑅𝑆 ) ) = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐴 𝑆 𝑦 ) ∧ ( 𝐵 𝑅 𝑥𝐵 𝑆 𝑦 ) ) } )
6 an4 ( ( ( 𝐴 𝑅 𝑥𝐴 𝑆 𝑦 ) ∧ ( 𝐵 𝑅 𝑥𝐵 𝑆 𝑦 ) ) ↔ ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) )
7 6 opabbii { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐴 𝑆 𝑦 ) ∧ ( 𝐵 𝑅 𝑥𝐵 𝑆 𝑦 ) ) } = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) }
8 5 7 eqtrdi ( ( 𝐴𝑉𝐵𝑊 ) → ( [ 𝐴 ] ( 𝑅𝑆 ) ∩ [ 𝐵 ] ( 𝑅𝑆 ) ) = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) } )
9 8 neeq1d ( ( 𝐴𝑉𝐵𝑊 ) → ( ( [ 𝐴 ] ( 𝑅𝑆 ) ∩ [ 𝐵 ] ( 𝑅𝑆 ) ) ≠ ∅ ↔ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) } ≠ ∅ ) )
10 opabn0 ( { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) } ≠ ∅ ↔ ∃ 𝑥𝑦 ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) )
11 exdistrv ( ∃ 𝑥𝑦 ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) ↔ ( ∃ 𝑥 ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ∃ 𝑦 ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) )
12 10 11 bitri ( { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) } ≠ ∅ ↔ ( ∃ 𝑥 ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ∃ 𝑦 ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) )
13 9 12 bitrdi ( ( 𝐴𝑉𝐵𝑊 ) → ( ( [ 𝐴 ] ( 𝑅𝑆 ) ∩ [ 𝐵 ] ( 𝑅𝑆 ) ) ≠ ∅ ↔ ( ∃ 𝑥 ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ∃ 𝑦 ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) ) )
14 brcosscnv2 ( ( 𝐴𝑉𝐵𝑊 ) → ( 𝐴 ( 𝑅𝑆 ) 𝐵 ↔ ( [ 𝐴 ] ( 𝑅𝑆 ) ∩ [ 𝐵 ] ( 𝑅𝑆 ) ) ≠ ∅ ) )
15 brcosscnv ( ( 𝐴𝑉𝐵𝑊 ) → ( 𝐴 𝑅 𝐵 ↔ ∃ 𝑥 ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ) )
16 brcosscnv ( ( 𝐴𝑉𝐵𝑊 ) → ( 𝐴 𝑆 𝐵 ↔ ∃ 𝑦 ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) )
17 15 16 anbi12d ( ( 𝐴𝑉𝐵𝑊 ) → ( ( 𝐴 𝑅 𝐵𝐴 𝑆 𝐵 ) ↔ ( ∃ 𝑥 ( 𝐴 𝑅 𝑥𝐵 𝑅 𝑥 ) ∧ ∃ 𝑦 ( 𝐴 𝑆 𝑦𝐵 𝑆 𝑦 ) ) ) )
18 13 14 17 3bitr4d ( ( 𝐴𝑉𝐵𝑊 ) → ( 𝐴 ( 𝑅𝑆 ) 𝐵 ↔ ( 𝐴 𝑅 𝐵𝐴 𝑆 𝐵 ) ) )