Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - start with the Axiom of Extensionality
Unordered and ordered pairs
raltp
Metamath Proof Explorer
Description: Convert a universal quantification over an unordered triple to a
conjunction. (Contributed by NM , 13-Sep-2011) (Revised by Mario
Carneiro , 23-Apr-2015)
Ref
Expression
Hypotheses
raltp.1
⊢ A ∈ V
raltp.2
⊢ B ∈ V
raltp.3
⊢ C ∈ V
raltp.4
⊢ x = A → φ ↔ ψ
raltp.5
⊢ x = B → φ ↔ χ
raltp.6
⊢ x = C → φ ↔ θ
Assertion
raltp
⊢ ∀ x ∈ A B C φ ↔ ψ ∧ χ ∧ θ
Proof
Step
Hyp
Ref
Expression
1
raltp.1
⊢ A ∈ V
2
raltp.2
⊢ B ∈ V
3
raltp.3
⊢ C ∈ V
4
raltp.4
⊢ x = A → φ ↔ ψ
5
raltp.5
⊢ x = B → φ ↔ χ
6
raltp.6
⊢ x = C → φ ↔ θ
7
4 5 6
raltpg
⊢ A ∈ V ∧ B ∈ V ∧ C ∈ V → ∀ x ∈ A B C φ ↔ ψ ∧ χ ∧ θ
8
1 2 3 7
mp3an
⊢ ∀ x ∈ A B C φ ↔ ψ ∧ χ ∧ θ