Theorem fmptsng 6983

Description: Express a singleton function in maps-to notation. Version of fmptsn 6982 allowing the value 𝐵 to depend on the variable 𝑥. (Contributed by AV, 27-Feb-2019.)

Hypothesis

Ref	Expression
fmptsng.1	⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)

Assertion

Ref	Expression
fmptsng	⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → {⟨𝐴, 𝐶⟩} = (𝑥 ∈ {𝐴} ↦ 𝐵))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐶

Allowed substitution hints:   𝐵(𝑥)   𝑉(𝑥)   𝑊(𝑥)

Proof of Theorem fmptsng

Dummy variables 𝑝 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		velsn 4557	. . . . 5 ⊢ (𝑥 ∈ {𝐴} ↔ 𝑥 = 𝐴)
2	1	bicomi 227	. . . 4 ⊢ (𝑥 = 𝐴 ↔ 𝑥 ∈ {𝐴})
3	2	anbi1i 627	. . 3 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ↔ (𝑥 ∈ {𝐴} ∧ 𝑦 = 𝐵))
4	3	opabbii 5120	. 2 ⊢ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)} = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ {𝐴} ∧ 𝑦 = 𝐵)}
5		velsn 4557	. . . . 5 ⊢ (𝑝 ∈ {⟨𝐴, 𝐶⟩} ↔ 𝑝 = ⟨𝐴, 𝐶⟩)
6		eqidd 2738	. . . . . . 7 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → 𝐴 = 𝐴)
7		eqidd 2738	. . . . . . 7 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → 𝐶 = 𝐶)
8		eqeq1 2741	. . . . . . . . . 10 ⊢ (𝑥 = 𝐴 → (𝑥 = 𝐴 ↔ 𝐴 = 𝐴))
9	8	adantr 484	. . . . . . . . 9 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐶) → (𝑥 = 𝐴 ↔ 𝐴 = 𝐴))
10		eqeq1 2741	. . . . . . . . . 10 ⊢ (𝑦 = 𝐶 → (𝑦 = 𝐵 ↔ 𝐶 = 𝐵))
11		fmptsng.1	. . . . . . . . . . 11 ⊢ (𝑥 = 𝐴 → 𝐵 = 𝐶)
12	11	eqeq2d 2748	. . . . . . . . . 10 ⊢ (𝑥 = 𝐴 → (𝐶 = 𝐵 ↔ 𝐶 = 𝐶))
13	10, 12	sylan9bbr 514	. . . . . . . . 9 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐶) → (𝑦 = 𝐵 ↔ 𝐶 = 𝐶))
14	9, 13	anbi12d 634	. . . . . . . 8 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐶) → ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ↔ (𝐴 = 𝐴 ∧ 𝐶 = 𝐶)))
15	14	opelopabga 5414	. . . . . . 7 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → (⟨𝐴, 𝐶⟩ ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)} ↔ (𝐴 = 𝐴 ∧ 𝐶 = 𝐶)))
16	6, 7, 15	mpbir2and 713	. . . . . 6 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → ⟨𝐴, 𝐶⟩ ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)})
17		eleq1 2825	. . . . . 6 ⊢ (𝑝 = ⟨𝐴, 𝐶⟩ → (𝑝 ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)} ↔ ⟨𝐴, 𝐶⟩ ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)}))
18	16, 17	syl5ibrcom 250	. . . . 5 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → (𝑝 = ⟨𝐴, 𝐶⟩ → 𝑝 ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)}))
19	5, 18	syl5bi 245	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → (𝑝 ∈ {⟨𝐴, 𝐶⟩} → 𝑝 ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)}))
20		elopab 5408	. . . . 5 ⊢ (𝑝 ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)} ↔ ∃𝑥∃𝑦(𝑝 = ⟨𝑥, 𝑦⟩ ∧ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)))
21		opeq12 4786	. . . . . . . . . 10 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → ⟨𝑥, 𝑦⟩ = ⟨𝐴, 𝐵⟩)
22	21	eqeq2d 2748	. . . . . . . . 9 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (𝑝 = ⟨𝑥, 𝑦⟩ ↔ 𝑝 = ⟨𝐴, 𝐵⟩))
23	11	adantr 484	. . . . . . . . . . . 12 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → 𝐵 = 𝐶)
24	23	opeq2d 4791	. . . . . . . . . . 11 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → ⟨𝐴, 𝐵⟩ = ⟨𝐴, 𝐶⟩)
25		opex 5348	. . . . . . . . . . . 12 ⊢ ⟨𝐴, 𝐶⟩ ∈ V
26	25	snid 4577	. . . . . . . . . . 11 ⊢ ⟨𝐴, 𝐶⟩ ∈ {⟨𝐴, 𝐶⟩}
27	24, 26	eqeltrdi 2846	. . . . . . . . . 10 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → ⟨𝐴, 𝐵⟩ ∈ {⟨𝐴, 𝐶⟩})
28		eleq1 2825	. . . . . . . . . 10 ⊢ (𝑝 = ⟨𝐴, 𝐵⟩ → (𝑝 ∈ {⟨𝐴, 𝐶⟩} ↔ ⟨𝐴, 𝐵⟩ ∈ {⟨𝐴, 𝐶⟩}))
29	27, 28	syl5ibrcom 250	. . . . . . . . 9 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (𝑝 = ⟨𝐴, 𝐵⟩ → 𝑝 ∈ {⟨𝐴, 𝐶⟩}))
30	22, 29	sylbid 243	. . . . . . . 8 ⊢ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) → (𝑝 = ⟨𝑥, 𝑦⟩ → 𝑝 ∈ {⟨𝐴, 𝐶⟩}))
31	30	impcom 411	. . . . . . 7 ⊢ ((𝑝 = ⟨𝑥, 𝑦⟩ ∧ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)) → 𝑝 ∈ {⟨𝐴, 𝐶⟩})
32	31	exlimivv 1940	. . . . . 6 ⊢ (∃𝑥∃𝑦(𝑝 = ⟨𝑥, 𝑦⟩ ∧ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)) → 𝑝 ∈ {⟨𝐴, 𝐶⟩})
33	32	a1i 11	. . . . 5 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → (∃𝑥∃𝑦(𝑝 = ⟨𝑥, 𝑦⟩ ∧ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)) → 𝑝 ∈ {⟨𝐴, 𝐶⟩}))
34	20, 33	syl5bi 245	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → (𝑝 ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)} → 𝑝 ∈ {⟨𝐴, 𝐶⟩}))
35	19, 34	impbid 215	. . 3 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → (𝑝 ∈ {⟨𝐴, 𝐶⟩} ↔ 𝑝 ∈ {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)}))
36	35	eqrdv 2735	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → {⟨𝐴, 𝐶⟩} = {⟨𝑥, 𝑦⟩ ∣ (𝑥 = 𝐴 ∧ 𝑦 = 𝐵)})
37		df-mpt 5136	. . 3 ⊢ (𝑥 ∈ {𝐴} ↦ 𝐵) = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ {𝐴} ∧ 𝑦 = 𝐵)}
38	37	a1i 11	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → (𝑥 ∈ {𝐴} ↦ 𝐵) = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ {𝐴} ∧ 𝑦 = 𝐵)})
39	4, 36, 38	3eqtr4a 2804	1 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐶 ∈ 𝑊) → {⟨𝐴, 𝐶⟩} = (𝑥 ∈ {𝐴} ↦ 𝐵))

Syntax hints:   → wi 4   ↔ wb 209   ∧ wa 399   = wceq 1543  ∃wex 1787   ∈ wcel 2110  {csn 4541  ⟨cop 4547  {copab 5115   ↦ cmpt 5135

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1803  ax-4 1817  ax-5 1918  ax-6 1976  ax-7 2016  ax-8 2112  ax-9 2120  ax-ext 2708  ax-sep 5192  ax-nul 5199  ax-pr 5322

This theorem depends on definitions:  df-bi 210  df-an 400  df-or 848  df-3an 1091  df-tru 1546  df-fal 1556  df-ex 1788  df-sb 2071  df-clab 2715  df-cleq 2729  df-clel 2816  df-rab 3070  df-v 3410  df-dif 3869  df-un 3871  df-nul 4238  df-if 4440  df-sn 4542  df-pr 4544  df-op 4548  df-opab 5116  df-mpt 5136

This theorem is referenced by:  mdet0pr  21489  m1detdiag  21494