Theorem funsndifnop 7138

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 5727	. . 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 6578	. . . . . . 7 ⊢ Fun {⟨𝐴, 𝐵⟩}
6		funeq 6545	. . . . . . 7 ⊢ (𝐺 = {⟨𝐴, 𝐵⟩} → (Fun 𝐺 ↔ Fun {⟨𝐴, 𝐵⟩}))
7	5, 6	mpbiri 261	. . . . . 6 ⊢ (𝐺 = {⟨𝐴, 𝐵⟩} → Fun 𝐺)
8	2, 7	ax-mp 5	. . . . 5 ⊢ Fun 𝐺
9		funeq 6545	. . . . . . 7 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (Fun 𝐺 ↔ Fun ⟨𝑥, 𝑦⟩))
10		vex 3461	. . . . . . . 8 ⊢ 𝑥 ∈ V
11		vex 3461	. . . . . . . 8 ⊢ 𝑦 ∈ V
12	10, 11	funop 7136	. . . . . . 7 ⊢ (Fun ⟨𝑥, 𝑦⟩ ↔ ∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}))
13	9, 12	bitrdi 290	. . . . . 6 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (Fun 𝐺 ↔ ∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩})))
14		eqeq2 2777	. . . . . . . . . . 11 ⊢ (⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩} → (𝐺 = ⟨𝑥, 𝑦⟩ ↔ 𝐺 = {⟨𝑎, 𝑎⟩}))
15		eqeq1 2769	. . . . . . . . . . . . 13 ⊢ (𝐺 = {⟨𝐴, 𝐵⟩} → (𝐺 = {⟨𝑎, 𝑎⟩} ↔ {⟨𝐴, 𝐵⟩} = {⟨𝑎, 𝑎⟩}))
16		opex 5436	. . . . . . . . . . . . . . 15 ⊢ ⟨𝐴, 𝐵⟩ ∈ V
17	16	sneqr 4801	. . . . . . . . . . . . . 14 ⊢ ({⟨𝐴, 𝐵⟩} = {⟨𝑎, 𝑎⟩} → ⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑎⟩)
18	3, 4	opth 5449	. . . . . . . . . . . . . . 15 ⊢ (⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑎⟩ ↔ (𝐴 = 𝑎 ∧ 𝐵 = 𝑎))
19		eqtr3 2787	. . . . . . . . . . . . . . . 16 ⊢ ((𝐴 = 𝑎 ∧ 𝐵 = 𝑎) → 𝐴 = 𝐵)
20	19	a1d 26	. . . . . . . . . . . . . . 15 ⊢ ((𝐴 = 𝑎 ∧ 𝐵 = 𝑎) → (𝑥 = {𝑎} → 𝐴 = 𝐵))
21	18, 20	sylbi 220	. . . . . . . . . . . . . 14 ⊢ (⟨𝐴, 𝐵⟩ = ⟨𝑎, 𝑎⟩ → (𝑥 = {𝑎} → 𝐴 = 𝐵))
22	17, 21	syl 18	. . . . . . . . . . . . 13 ⊢ ({⟨𝐴, 𝐵⟩} = {⟨𝑎, 𝑎⟩} → (𝑥 = {𝑎} → 𝐴 = 𝐵))
23	15, 22	biimtrdi 256	. . . . . . . . . . . 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	biimtrdi 256	. . . . . . . . . 10 ⊢ (⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩} → (𝐺 = ⟨𝑥, 𝑦⟩ → (𝑥 = {𝑎} → 𝐴 = 𝐵)))
26	25	com23 87	. . . . . . . . 9 ⊢ (⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩} → (𝑥 = {𝑎} → (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵)))
27	26	impcom 412	. . . . . . . 8 ⊢ ((𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}) → (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵))
28	27	exlimiv 1953	. . . . . . 7 ⊢ (∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}) → (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵))
29	28	com12 33	. . . . . 6 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (∃𝑎(𝑥 = {𝑎} ∧ ⟨𝑥, 𝑦⟩ = {⟨𝑎, 𝑎⟩}) → 𝐴 = 𝐵))
30	13, 29	sylbid 243	. . . . 5 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → (Fun 𝐺 → 𝐴 = 𝐵))
31	8, 30	mpi 21	. . . 4 ⊢ (𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵)
32	31	exlimivv 1955	. . 3 ⊢ (∃𝑥∃𝑦 𝐺 = ⟨𝑥, 𝑦⟩ → 𝐴 = 𝐵)
33	1, 32	sylbi 220	. 2 ⊢ (𝐺 ∈ (V × V) → 𝐴 = 𝐵)
34	33	necon3ai 2985	1 ⊢ (𝐴 ≠ 𝐵 → ¬ 𝐺 ∈ (V × V))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 400   = wceq 1563  ∃wex 1802   ∈ wcel 2145   ≠ wne 2960  Vcvv 3457  {csn 4585  ⟨cop 4591   × cxp 5650  Fun wfun 6519

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1818  ax-4 1832  ax-5 1933  ax-6 1990  ax-7 2031  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2737  ax-sep 5251  ax-nul 5261  ax-pr 5395

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1103  df-tru 1566  df-fal 1576  df-ex 1803  df-nf 1807  df-sb 2094  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ne 2961  df-ral 3080  df-rex 3090  df-reu 3371  df-rab 3418  df-v 3459  df-sbc 3748  df-csb 3856  df-dif 3910  df-un 3912  df-in 3914  df-ss 3924  df-nul 4289  df-if 4484  df-sn 4586  df-pr 4588  df-op 4592  df-uni 4869  df-iun 4954  df-br 5106  df-opab 5168  df-mpt 5187  df-id 5547  df-xp 5658  df-rel 5659  df-cnv 5660  df-co 5661  df-dm 5662  df-rn 5663  df-iota 6481  df-fun 6527  df-fn 6528  df-f 6529  df-f1 6530  df-fo 6531  df-f1o 6532  df-fv 6533

This theorem is referenced by:  funsneqopb  7139  snstrvtxval  29296  snstriedgval  29297