Theorem s1dmALT 14535

Description: Alternate version of s1dm 14534, having a shorter proof, but requiring that 𝐴 is a set. (Contributed by AV, 9-Jan-2020.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
s1dmALT	⊢ (𝐴 ∈ 𝑆 → dom ⟨“𝐴”⟩ = {0})

Proof of Theorem s1dmALT

Step	Hyp	Ref	Expression
1		s1val 14524	. . 3 ⊢ (𝐴 ∈ 𝑆 → ⟨“𝐴”⟩ = {⟨0, 𝐴⟩})
2	1	dmeqd 5854	. 2 ⊢ (𝐴 ∈ 𝑆 → dom ⟨“𝐴”⟩ = dom {⟨0, 𝐴⟩})
3		dmsnopg 6171	. 2 ⊢ (𝐴 ∈ 𝑆 → dom {⟨0, 𝐴⟩} = {0})
4	2, 3	eqtrd 2771	1 ⊢ (𝐴 ∈ 𝑆 → dom ⟨“𝐴”⟩ = {0})

Syntax hints:   → wi 4   = wceq 1541   ∈ wcel 2113  {csn 4580  ⟨cop 4586  dom cdm 5624  0cc0 11028  ⟨“cs1 14521

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-10 2146  ax-12 2184  ax-ext 2708  ax-sep 5241  ax-nul 5251  ax-pr 5377

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-nf 1785  df-sb 2068  df-mo 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-ral 3052  df-rex 3061  df-rab 3400  df-v 3442  df-dif 3904  df-un 3906  df-ss 3918  df-nul 4286  df-if 4480  df-sn 4581  df-pr 4583  df-op 4587  df-uni 4864  df-br 5099  df-opab 5161  df-id 5519  df-xp 5630  df-rel 5631  df-cnv 5632  df-co 5633  df-dm 5634  df-iota 6448  df-fun 6494  df-fv 6500  df-s1 14522

This theorem is referenced by: (None)