Theorem r19.3rmv 3400

Description: Restricted quantification of wff not containing quantified variable. (Contributed by Jim Kingdon, 6-Aug-2018.)

Assertion

Ref	Expression
r19.3rmv	⊢ (∃𝑦 𝑦 ∈ 𝐴 → (𝜑 ↔ ∀𝑥 ∈ 𝐴 𝜑))

Distinct variable groups:   𝑥,𝐴   𝑦,𝐴   𝜑,𝑥

Allowed substitution hint:   𝜑(𝑦)

Proof of Theorem r19.3rmv

Step	Hyp	Ref	Expression
1		nfv 1476	. 2 ⊢ Ⅎ𝑥𝜑
2	1	r19.3rm 3398	1 ⊢ (∃𝑦 𝑦 ∈ 𝐴 → (𝜑 ↔ ∀𝑥 ∈ 𝐴 𝜑))

Syntax hints:   → wi 4   ↔ wb 104  ∃wex 1436   ∈ wcel 1448  ∀wral 2375

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1391  ax-7 1392  ax-gen 1393  ax-ie1 1437  ax-ie2 1438  ax-8 1450  ax-4 1455  ax-17 1474  ax-i9 1478  ax-ial 1482  ax-i5r 1483  ax-ext 2082

This theorem depends on definitions:  df-bi 116  df-nf 1405  df-cleq 2093  df-clel 2096  df-ral 2380

This theorem is referenced by:  iinconstm  3769  exmidsssnc  4064  cnvpom  5017  ssfilem  6698  diffitest  6710  inffiexmid  6729  ctssexmid  6936  caucvgsrlemasr  7485  resqrexlemgt0  10632