Theorem s1prc 14642

Description: Value of a singleton word if the symbol is a proper class. (Contributed by AV, 26-Mar-2022.)

Assertion

Ref	Expression
s1prc	⊢ (¬ 𝐴 ∈ V → ⟨“𝐴”⟩ = ⟨“∅”⟩)

Proof of Theorem s1prc

Step	Hyp	Ref	Expression
1		ids1 14635	. 2 ⊢ ⟨“𝐴”⟩ = ⟨“( I ‘𝐴)”⟩
2		fvprc 6898	. . 3 ⊢ (¬ 𝐴 ∈ V → ( I ‘𝐴) = ∅)
3	2	s1eqd 14639	. 2 ⊢ (¬ 𝐴 ∈ V → ⟨“( I ‘𝐴)”⟩ = ⟨“∅”⟩)
4	1, 3	eqtrid 2789	1 ⊢ (¬ 𝐴 ∈ V → ⟨“𝐴”⟩ = ⟨“∅”⟩)

Syntax hints:  ¬ wn 3   → wi 4   = wceq 1540   ∈ wcel 2108  Vcvv 3480  ∅c0 4333   I cid 5577  ‘cfv 6561  ⟨“cs1 14633

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-10 2141  ax-11 2157  ax-12 2177  ax-ext 2708  ax-sep 5296  ax-nul 5306  ax-pr 5432

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2065  df-mo 2540  df-eu 2569  df-clab 2715  df-cleq 2729  df-clel 2816  df-ne 2941  df-ral 3062  df-rex 3071  df-rab 3437  df-v 3482  df-dif 3954  df-un 3956  df-ss 3968  df-nul 4334  df-if 4526  df-sn 4627  df-pr 4629  df-op 4633  df-uni 4908  df-br 5144  df-opab 5206  df-id 5578  df-xp 5691  df-rel 5692  df-cnv 5693  df-co 5694  df-dm 5695  df-iota 6514  df-fun 6563  df-fv 6569  df-s1 14634

This theorem is referenced by: (None)