Theorem albidh 1409

Description: Formula-building rule for universal quantifier (deduction rule). (Contributed by NM, 5-Aug-1993.)

Hypotheses

Ref	Expression
albidh.1	⊢ (𝜑 → ∀𝑥𝜑)
albidh.2	⊢ (𝜑 → (𝜓 ↔ 𝜒))

Assertion

Ref	Expression
albidh	⊢ (𝜑 → (∀𝑥𝜓 ↔ ∀𝑥𝜒))

Proof of Theorem albidh

Step	Hyp	Ref	Expression
1		albidh.1	. . 3 ⊢ (𝜑 → ∀𝑥𝜑)
2		albidh.2	. . 3 ⊢ (𝜑 → (𝜓 ↔ 𝜒))
3	1, 2	alrimih 1398	. 2 ⊢ (𝜑 → ∀𝑥(𝜓 ↔ 𝜒))
4		albi 1397	. 2 ⊢ (∀𝑥(𝜓 ↔ 𝜒) → (∀𝑥𝜓 ↔ ∀𝑥𝜒))
5	3, 4	syl 14	1 ⊢ (𝜑 → (∀𝑥𝜓 ↔ ∀𝑥𝜒))

Syntax hints:   → wi 4   ↔ wb 103  ∀wal 1282

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-5 1376  ax-gen 1378

This theorem depends on definitions:  df-bi 115

This theorem is referenced by:  nfbidf  1472  albid  1546  dral2  1659  ax11v2  1741  albidv  1745  equs5or  1751  sbal2  1939  eubidh  1947