Metamath Proof Explorer


Theorem otthne

Description: Contrapositive of the ordered triple theorem. (Contributed by Scott Fenton, 21-Aug-2024)

Ref Expression
Hypotheses otthne.1 𝐴 ∈ V
otthne.2 𝐵 ∈ V
otthne.3 𝐶 ∈ V
Assertion otthne ( ⟨ ⟨ 𝐴 , 𝐵 ⟩ , 𝐶 ⟩ ≠ ⟨ ⟨ 𝐷 , 𝐸 ⟩ , 𝐹 ⟩ ↔ ( 𝐴𝐷𝐵𝐸𝐶𝐹 ) )

Proof

Step Hyp Ref Expression
1 otthne.1 𝐴 ∈ V
2 otthne.2 𝐵 ∈ V
3 otthne.3 𝐶 ∈ V
4 1 2 opthne ( ⟨ 𝐴 , 𝐵 ⟩ ≠ ⟨ 𝐷 , 𝐸 ⟩ ↔ ( 𝐴𝐷𝐵𝐸 ) )
5 4 orbi1i ( ( ⟨ 𝐴 , 𝐵 ⟩ ≠ ⟨ 𝐷 , 𝐸 ⟩ ∨ 𝐶𝐹 ) ↔ ( ( 𝐴𝐷𝐵𝐸 ) ∨ 𝐶𝐹 ) )
6 opex 𝐴 , 𝐵 ⟩ ∈ V
7 6 3 opthne ( ⟨ ⟨ 𝐴 , 𝐵 ⟩ , 𝐶 ⟩ ≠ ⟨ ⟨ 𝐷 , 𝐸 ⟩ , 𝐹 ⟩ ↔ ( ⟨ 𝐴 , 𝐵 ⟩ ≠ ⟨ 𝐷 , 𝐸 ⟩ ∨ 𝐶𝐹 ) )
8 df-3or ( ( 𝐴𝐷𝐵𝐸𝐶𝐹 ) ↔ ( ( 𝐴𝐷𝐵𝐸 ) ∨ 𝐶𝐹 ) )
9 5 7 8 3bitr4i ( ⟨ ⟨ 𝐴 , 𝐵 ⟩ , 𝐶 ⟩ ≠ ⟨ ⟨ 𝐷 , 𝐸 ⟩ , 𝐹 ⟩ ↔ ( 𝐴𝐷𝐵𝐸𝐶𝐹 ) )