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 ) |
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 ) |