Theorem r19.23 3259

Description: Restricted quantifier version of 19.23 2247. See r19.23v 3189 for a version requiring fewer axioms. (Contributed by NM, 22-Oct-2010.) (Proof shortened by Mario Carneiro, 8-Oct-2016.)

Hypothesis

Ref	Expression
r19.23.1	⊢ Ⅎ𝑥𝜓

Assertion

Ref	Expression
r19.23	⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ (∃𝑥 ∈ 𝐴 𝜑 → 𝜓))

Proof of Theorem r19.23

Step	Hyp	Ref	Expression
1		r19.23.1	. 2 ⊢ Ⅎ𝑥𝜓
2		r19.23t 3258	. 2 ⊢ (Ⅎ𝑥𝜓 → (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ (∃𝑥 ∈ 𝐴 𝜑 → 𝜓)))
3	1, 2	ax-mp 5	1 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ (∃𝑥 ∈ 𝐴 𝜑 → 𝜓))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209  Ⅎwnf 1815  ∀wral 3076  ∃wrex 3086

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-12 2212

This proof depends on definitions:  df-bi 210  df-an 402  df-ex 1812  df-nf 1816  df-ral 3077  df-rex 3087

This theorem is used by:  rexlimi  3262  iunssf  5000  iunssfOLD  5001  ralxp3f  8161