Theorem upgrex 15888

Description: An edge is an unordered pair of vertices. (Contributed by Mario Carneiro, 11-Mar-2015.) (Revised by AV, 10-Oct-2020.)

Hypotheses

Ref	Expression
isupgr.v	⊢ 𝑉 = (Vtx‘𝐺)
isupgr.e	⊢ 𝐸 = (iEdg‘𝐺)

Assertion

Ref	Expression
upgrex	⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ 𝑉 (𝐸‘𝐹) = {𝑥, 𝑦})

Distinct variable groups:   𝑥,𝐺   𝑥,𝑉   𝑥,𝐸   𝑥,𝐹   𝑥,𝐴,𝑦   𝑦,𝐸   𝑦,𝐹   𝑦,𝐺   𝑦,𝑉

Proof of Theorem upgrex

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		isupgr.v	. . . . 5 ⊢ 𝑉 = (Vtx‘𝐺)
2		isupgr.e	. . . . 5 ⊢ 𝐸 = (iEdg‘𝐺)
3	1, 2	upgr1or2 15886	. . . 4 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → ((𝐸‘𝐹) ≈ 1o ∨ (𝐸‘𝐹) ≈ 2o))
4		en1 6941	. . . . . . 7 ⊢ ((𝐸‘𝐹) ≈ 1o ↔ ∃𝑧(𝐸‘𝐹) = {𝑧})
5		dfsn2 3680	. . . . . . . . 9 ⊢ {𝑧} = {𝑧, 𝑧}
6	5	eqeq2i 2240	. . . . . . . 8 ⊢ ((𝐸‘𝐹) = {𝑧} ↔ (𝐸‘𝐹) = {𝑧, 𝑧})
7	6	exbii 1651	. . . . . . 7 ⊢ (∃𝑧(𝐸‘𝐹) = {𝑧} ↔ ∃𝑧(𝐸‘𝐹) = {𝑧, 𝑧})
8	4, 7	bitri 184	. . . . . 6 ⊢ ((𝐸‘𝐹) ≈ 1o ↔ ∃𝑧(𝐸‘𝐹) = {𝑧, 𝑧})
9		preq2 3744	. . . . . . . . . . 11 ⊢ (𝑦 = 𝑧 → {𝑧, 𝑦} = {𝑧, 𝑧})
10	9	eqeq2d 2241	. . . . . . . . . 10 ⊢ (𝑦 = 𝑧 → ((𝐸‘𝐹) = {𝑧, 𝑦} ↔ (𝐸‘𝐹) = {𝑧, 𝑧}))
11	10	spcegv 2891	. . . . . . . . 9 ⊢ (𝑧 ∈ V → ((𝐸‘𝐹) = {𝑧, 𝑧} → ∃𝑦(𝐸‘𝐹) = {𝑧, 𝑦}))
12	11	elv 2803	. . . . . . . 8 ⊢ ((𝐸‘𝐹) = {𝑧, 𝑧} → ∃𝑦(𝐸‘𝐹) = {𝑧, 𝑦})
13		preq1 3743	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝑧 → {𝑥, 𝑦} = {𝑧, 𝑦})
14	13	eqeq2d 2241	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑧 → ((𝐸‘𝐹) = {𝑥, 𝑦} ↔ (𝐸‘𝐹) = {𝑧, 𝑦}))
15	14	exbidv 1871	. . . . . . . . . 10 ⊢ (𝑥 = 𝑧 → (∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦} ↔ ∃𝑦(𝐸‘𝐹) = {𝑧, 𝑦}))
16	15	spcegv 2891	. . . . . . . . 9 ⊢ (𝑧 ∈ V → (∃𝑦(𝐸‘𝐹) = {𝑧, 𝑦} → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦}))
17	16	elv 2803	. . . . . . . 8 ⊢ (∃𝑦(𝐸‘𝐹) = {𝑧, 𝑦} → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦})
18	12, 17	syl 14	. . . . . . 7 ⊢ ((𝐸‘𝐹) = {𝑧, 𝑧} → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦})
19	18	exlimiv 1644	. . . . . 6 ⊢ (∃𝑧(𝐸‘𝐹) = {𝑧, 𝑧} → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦})
20	8, 19	sylbi 121	. . . . 5 ⊢ ((𝐸‘𝐹) ≈ 1o → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦})
21		en2 6963	. . . . 5 ⊢ ((𝐸‘𝐹) ≈ 2o → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦})
22	20, 21	jaoi 721	. . . 4 ⊢ (((𝐸‘𝐹) ≈ 1o ∨ (𝐸‘𝐹) ≈ 2o) → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦})
23	3, 22	syl 14	. . 3 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → ∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦})
24		simp1 1021	. . . . . . . . 9 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → 𝐺 ∈ UPGraph)
25		simp3 1023	. . . . . . . . . 10 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → 𝐹 ∈ 𝐴)
26		fndm 5416	. . . . . . . . . . 11 ⊢ (𝐸 Fn 𝐴 → dom 𝐸 = 𝐴)
27	26	3ad2ant2 1043	. . . . . . . . . 10 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → dom 𝐸 = 𝐴)
28	25, 27	eleqtrrd 2309	. . . . . . . . 9 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → 𝐹 ∈ dom 𝐸)
29	1, 2	upgrss 15884	. . . . . . . . 9 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐹 ∈ dom 𝐸) → (𝐸‘𝐹) ⊆ 𝑉)
30	24, 28, 29	syl2anc 411	. . . . . . . 8 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → (𝐸‘𝐹) ⊆ 𝑉)
31	30	adantr 276	. . . . . . 7 ⊢ (((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}) → (𝐸‘𝐹) ⊆ 𝑉)
32		vex 2802	. . . . . . . . 9 ⊢ 𝑥 ∈ V
33	32	prid1 3772	. . . . . . . 8 ⊢ 𝑥 ∈ {𝑥, 𝑦}
34		simpr 110	. . . . . . . 8 ⊢ (((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}) → (𝐸‘𝐹) = {𝑥, 𝑦})
35	33, 34	eleqtrrid 2319	. . . . . . 7 ⊢ (((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}) → 𝑥 ∈ (𝐸‘𝐹))
36	31, 35	sseldd 3225	. . . . . 6 ⊢ (((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}) → 𝑥 ∈ 𝑉)
37		vex 2802	. . . . . . . . 9 ⊢ 𝑦 ∈ V
38	37	prid2 3773	. . . . . . . 8 ⊢ 𝑦 ∈ {𝑥, 𝑦}
39	38, 34	eleqtrrid 2319	. . . . . . 7 ⊢ (((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}) → 𝑦 ∈ (𝐸‘𝐹))
40	31, 39	sseldd 3225	. . . . . 6 ⊢ (((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}) → 𝑦 ∈ 𝑉)
41	36, 40, 34	jca31 309	. . . . 5 ⊢ (((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}) → ((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}))
42	41	ex 115	. . . 4 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → ((𝐸‘𝐹) = {𝑥, 𝑦} → ((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) ∧ (𝐸‘𝐹) = {𝑥, 𝑦})))
43	42	2eximdv 1928	. . 3 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → (∃𝑥∃𝑦(𝐸‘𝐹) = {𝑥, 𝑦} → ∃𝑥∃𝑦((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) ∧ (𝐸‘𝐹) = {𝑥, 𝑦})))
44	23, 43	mpd 13	. 2 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → ∃𝑥∃𝑦((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}))
45		r2ex 2550	. 2 ⊢ (∃𝑥 ∈ 𝑉 ∃𝑦 ∈ 𝑉 (𝐸‘𝐹) = {𝑥, 𝑦} ↔ ∃𝑥∃𝑦((𝑥 ∈ 𝑉 ∧ 𝑦 ∈ 𝑉) ∧ (𝐸‘𝐹) = {𝑥, 𝑦}))
46	44, 45	sylibr 134	1 ⊢ ((𝐺 ∈ UPGraph ∧ 𝐸 Fn 𝐴 ∧ 𝐹 ∈ 𝐴) → ∃𝑥 ∈ 𝑉 ∃𝑦 ∈ 𝑉 (𝐸‘𝐹) = {𝑥, 𝑦})

Syntax hints:   → wi 4   ∧ wa 104   ∨ wo 713   ∧ w3a 1002   = wceq 1395  ∃wex 1538   ∈ wcel 2200  ∃wrex 2509  Vcvv 2799   ⊆ wss 3197  {csn 3666  {cpr 3667   class class class wbr 4082  dom cdm 4716   Fn wfn 5309  ‘cfv 5314  1_oc1o 6545  2_oc2o 6546   ≈ cen 6875  Vtxcvtx 15798  iEdgciedg 15799  UPGraphcupgr 15876

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4201  ax-nul 4209  ax-pow 4257  ax-pr 4292  ax-un 4521  ax-setind 4626  ax-cnex 8078  ax-resscn 8079  ax-1cn 8080  ax-1re 8081  ax-icn 8082  ax-addcl 8083  ax-addrcl 8084  ax-mulcl 8085  ax-addcom 8087  ax-mulcom 8088  ax-addass 8089  ax-mulass 8090  ax-distr 8091  ax-i2m1 8092  ax-1rid 8094  ax-0id 8095  ax-rnegex 8096  ax-cnre 8098

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-ral 2513  df-rex 2514  df-reu 2515  df-rab 2517  df-v 2801  df-sbc 3029  df-csb 3125  df-dif 3199  df-un 3201  df-in 3203  df-ss 3210  df-nul 3492  df-if 3603  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3888  df-int 3923  df-br 4083  df-opab 4145  df-mpt 4146  df-tr 4182  df-id 4381  df-iord 4454  df-on 4456  df-suc 4459  df-xp 4722  df-rel 4723  df-cnv 4724  df-co 4725  df-dm 4726  df-rn 4727  df-res 4728  df-ima 4729  df-iota 5274  df-fun 5316  df-fn 5317  df-f 5318  df-f1 5319  df-fo 5320  df-f1o 5321  df-fv 5322  df-riota 5947  df-ov 5997  df-oprab 5998  df-mpo 5999  df-1st 6276  df-2nd 6277  df-1o 6552  df-2o 6553  df-en 6878  df-sub 8307  df-inn 9099  df-2 9157  df-3 9158  df-4 9159  df-5 9160  df-6 9161  df-7 9162  df-8 9163  df-9 9164  df-n0 9358  df-dec 9567  df-ndx 13021  df-slot 13022  df-base 13024  df-edgf 15791  df-vtx 15800  df-iedg 15801  df-upgren 15878

This theorem is referenced by:  upgredg  15927