Theorem albidh 1898

Description: Formula-building rule for universal quantifier (deduction form). (Contributed by NM, 26-May-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 1856	. 2 ⊢ (𝜑 → ∀𝑥(𝜓 ↔ 𝜒))
4		albi 1850	. 2 ⊢ (∀𝑥(𝜓 ↔ 𝜒) → (∀𝑥𝜓 ↔ ∀𝑥𝜒))
5	3, 4	syl 18	1 ⊢ (𝜑 → (∀𝑥𝜓 ↔ ∀𝑥𝜒))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209  ∀wal 1567

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841

This proof depends on definitions:  df-bi 210

This theorem is used by:  albidv  1954  albid  2261  dral1v  2401  bj-equsalvwd  37804  dral2-o  40130  ax12indalem  40145  ax12inda2ALT  40146  ax12inda  40148