Theorem s1dmALT 14624

Description: Alternate version of s1dm 14623, 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 14613	. . 3 ⊢ (𝐴 ∈ 𝑆 → ⟨“𝐴”⟩ = {⟨0, 𝐴⟩})
2	1	dmeqd 5882	. 2 ⊢ (𝐴 ∈ 𝑆 → dom ⟨“𝐴”⟩ = dom {⟨0, 𝐴⟩})
3		dmsnopg 6201	. 2 ⊢ (𝐴 ∈ 𝑆 → dom {⟨0, 𝐴⟩} = {0})
4	2, 3	eqtrd 2798	1 ⊢ (𝐴 ∈ 𝑆 → dom ⟨“𝐴”⟩ = {0})

Syntax hints:   → wi 4   = wceq 1561   ∈ wcel 2143  {csn 4583  ⟨cop 4589  dom cdm 5648  0cc0 11074  ⟨“cs1 14610

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1816  ax-4 1830  ax-5 1931  ax-6 1988  ax-7 2029  ax-8 2145  ax-9 2153  ax-10 2176  ax-12 2213  ax-ext 2735  ax-sep 5247  ax-pr 5391

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3an 1101  df-tru 1564  df-fal 1574  df-ex 1801  df-nf 1805  df-sb 2092  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2838  df-ral 3078  df-rex 3088  df-rab 3416  df-v 3457  df-dif 3908  df-un 3910  df-in 3912  df-ss 3922  df-nul 4287  df-if 4482  df-sn 4584  df-pr 4586  df-op 4590  df-uni 4867  df-br 5102  df-opab 5164  df-id 5543  df-xp 5654  df-rel 5655  df-cnv 5656  df-co 5657  df-dm 5658  df-iota 6478  df-fun 6524  df-fv 6530  df-s1 14611

This theorem is referenced by: (None)