Metamath Proof Explorer


Theorem bj-hbaeb

Description: Biconditional version of hbae . (Contributed by BJ, 6-Oct-2018) (Proof modification is discouraged.)

Ref Expression
Assertion bj-hbaeb ( ∀ 𝑥 𝑥 = 𝑦 ↔ ∀ 𝑧 ∀ 𝑥 𝑥 = 𝑦 )

Proof

Step Hyp Ref Expression
1 bj-hbaeb2 ⊢ ( ∀ 𝑥 𝑥 = 𝑦 ↔ ∀ 𝑥 ∀ 𝑧 𝑥 = 𝑦 )
2 alcom ⊢ ( ∀ 𝑥 ∀ 𝑧 𝑥 = 𝑦 ↔ ∀ 𝑧 ∀ 𝑥 𝑥 = 𝑦 )
3 1 2 bitri ⊢ ( ∀ 𝑥 𝑥 = 𝑦 ↔ ∀ 𝑧 ∀ 𝑥 𝑥 = 𝑦 )