Theorem funsndifnop 7149

Description: A singleton of an ordered pair is not an ordered pair if the components are different. (Contributed by AV, 23-Sep-2020.) (Avoid depending on this detail.)

Hypotheses

Ref	Expression
funsndifnop.a	⊢ 𝐴 ∈ V
funsndifnop.b	⊢ 𝐵 ∈ V
funsndifnop.g	⊢ 𝐺 = {⟨𝐴, 𝐵⟩}

Assertion

Ref	Expression
funsndifnop	⊢ (𝐴 ≠ 𝐵 → ¬ 𝐺 ∈ (V × V))

Proof of Theorem funsndifnop

Dummy variables 𝑎 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		elvv 5751	. . 3 ⊢ (𝐺 ∈ (V × V) ↔ ∃𝑥∃𝑦 𝐺 = ⟨𝑥, 𝑦⟩)
2		funsndifnop.g	. . . . . 6 ⊢ 𝐺 = {⟨𝐴, 𝐵⟩}
3		funsndifnop.a	. . . . . . . 8 ⊢ 𝐴 ∈ V
4		funsndifnop.b	. . . . . . . 8 ⊢ 𝐵 ∈ V
5	3, 4	funsn 6602	. . . . . . 7 ⊢ Fun {⟨𝐴, 𝐵⟩}
6		funeq 6569	. . . . . . 7 ⊢ (𝐺 = {⟨𝐴, 𝐵⟩} → (Fun 𝐺 ↔ Fun {⟨𝐴, 𝐵⟩}))
7	5, 6	mpbiri 258	. . . . . 6 ⊢ (𝐺 = {⟨𝐴, 𝐵⟩} → Fun 𝐺)
8	2, 7	ax-mp 5	. . . . 5 ⊢ Fun 𝐺
9		funeq 6569	. . . . . . 7 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (Fun 𝐺 ↔ Fun ⟨𝑥, 𝑦⟩))
10		vex 3479	. . . . . . . 8 ⊢ 𝑥 ∈ V
11		vex 3479	. . . . . . . 8 ⊢ 𝑦 ∈ V
12	10, 11	funop 7147	. . . . . . 7 ⊢ (Fun ⟨𝑥, 𝑦⟩ ↔ ∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}))
13	9, 12	bitrdi 287	. . . . . 6 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (Fun 𝐺 ↔ ∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩})))
14		eqeq2 2745	. . . . . . . . . . 11 ⊢ (⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩} → (𝐺 = ⟨𝑥, 𝑦⟩ ↔ 𝐺 = {⟨𝑎, 𝑎⟩}))
15		eqeq1 2737	. . . . . . . . . . . . 13 ⊢ (𝐺 = {⟨𝐴, 𝐵⟩} → (𝐺 = {⟨𝑎, 𝑎⟩} ↔ {⟨𝐴, 𝐵⟩} = {⟨𝑎, 𝑎⟩}))
16		opex 5465	. . . . . . . . . . . . . . 15 ⊢ ⟨𝐴, 𝐵⟩ ∈ V
17	16	sneqr 4842	. . . . . . . . . . . . . 14 ⊢ ({⟨𝐴, 𝐵⟩} = {⟨𝑎, 𝑎⟩} → ⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑎⟩)
18	3, 4	opth 5477	. . . . . . . . . . . . . . 15 ⊢ (⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑎⟩ ↔ (𝐴 = 𝑎 ∧ 𝐵 = 𝑎))
19		eqtr3 2759	. . . . . . . . . . . . . . . 16 ⊢ ((𝐴 = 𝑎 ∧ 𝐵 = 𝑎) → 𝐴 = 𝐵)
20	19	a1d 25	. . . . . . . . . . . . . . 15 ⊢ ((𝐴 = 𝑎 ∧ 𝐵 = 𝑎) → (𝑥 = {𝑎} → 𝐴 = 𝐵))
21	18, 20	sylbi 216	. . . . . . . . . . . . . 14 ⊢ (⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑎⟩ → (𝑥 = {𝑎} → 𝐴 = 𝐵))
22	17, 21	syl 17	. . . . . . . . . . . . 13 ⊢ ({⟨𝐴, 𝐵⟩} = {⟨𝑎, 𝑎⟩} → (𝑥 = {𝑎} → 𝐴 = 𝐵))
23	15, 22	syl6bi 253	. . . . . . . . . . . 12 ⊢ (𝐺 = {⟨𝐴, 𝐵⟩} → (𝐺 = {⟨𝑎, 𝑎⟩} → (𝑥 = {𝑎} → 𝐴 = 𝐵)))
24	2, 23	ax-mp 5	. . . . . . . . . . 11 ⊢ (𝐺 = {⟨𝑎, 𝑎⟩} → (𝑥 = {𝑎} → 𝐴 = 𝐵))
25	14, 24	syl6bi 253	. . . . . . . . . 10 ⊢ (⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩} → (𝐺 = ⟨𝑥, 𝑦⟩ → (𝑥 = {𝑎} → 𝐴 = 𝐵)))
26	25	com23 86	. . . . . . . . 9 ⊢ (⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩} → (𝑥 = {𝑎} → (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵)))
27	26	impcom 409	. . . . . . . 8 ⊢ ((𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}) → (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵))
28	27	exlimiv 1934	. . . . . . 7 ⊢ (∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}) → (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵))
29	28	com12 32	. . . . . 6 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}) → 𝐴 = 𝐵))
30	13, 29	sylbid 239	. . . . 5 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (Fun 𝐺 → 𝐴 = 𝐵))
31	8, 30	mpi 20	. . . 4 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵)
32	31	exlimivv 1936	. . 3 ⊢ (∃𝑥∃𝑦 𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵)
33	1, 32	sylbi 216	. 2 ⊢ (𝐺 ∈ (V × V) → 𝐴 = 𝐵)
34	33	necon3ai 2966	1 ⊢ (𝐴 ≠ 𝐵 → ¬ 𝐺 ∈ (V × V))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 397   = wceq 1542  ∃wex 1782   ∈ wcel 2107   ≠ wne 2941  Vcvv 3475  {csn 4629  ⟨cop 4635   × cxp 5675  Fun wfun 6538

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2109  ax-9 2117  ax-10 2138  ax-11 2155  ax-12 2172  ax-ext 2704  ax-sep 5300  ax-nul 5307  ax-pr 5428

This theorem depends on definitions:  df-bi 206  df-an 398  df-or 847  df-3an 1090  df-tru 1545  df-fal 1555  df-ex 1783  df-nf 1787  df-sb 2069  df-mo 2535  df-eu 2564  df-clab 2711  df-cleq 2725  df-clel 2811  df-nfc 2886  df-ne 2942  df-ral 3063  df-rex 3072  df-reu 3378  df-rab 3434  df-v 3477  df-sbc 3779  df-csb 3895  df-dif 3952  df-un 3954  df-in 3956  df-ss 3966  df-nul 4324  df-if 4530  df-sn 4630  df-pr 4632  df-op 4636  df-uni 4910  df-iun 5000  df-br 5150  df-opab 5212  df-mpt 5233  df-id 5575  df-xp 5683  df-rel 5684  df-cnv 5685  df-co 5686  df-dm 5687  df-rn 5688  df-iota 6496  df-fun 6546  df-fn 6547  df-f 6548  df-f1 6549  df-fo 6550  df-f1o 6551  df-fv 6552

This theorem is referenced by:  funsneqopb  7150  snstrvtxval  28297  snstriedgval  28298