Theorem prsprel 48395

Description: The elements of a pair from the set of all unordered pairs over a given set 𝑉 are elements of the set 𝑉. (Contributed by AV, 22-Nov-2021.)

Assertion

Ref	Expression
prsprel	⊢ (({𝑋, 𝑌} ∈ (Pairs‘𝑉) ∧ (𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊)) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉))

Proof of Theorem prsprel

Dummy variables 𝑎 𝑏 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		sprel 48392	. . 3 ⊢ ({𝑋, 𝑌} ∈ (Pairs‘𝑉) → ∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 {𝑋, 𝑌} = {𝑎, 𝑏})
2		preq12bg 4816	. . . . . . 7 ⊢ (((𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → ({𝑋, 𝑌} = {𝑎, 𝑏} ↔ ((𝑋 = 𝑎 ∧ 𝑌 = 𝑏) ∨ (𝑋 = 𝑏 ∧ 𝑌 = 𝑎))))
3		eleq1 2850	. . . . . . . . . . . . 13 ⊢ (𝑎 = 𝑋 → (𝑎 ∈ 𝑉 ↔ 𝑋 ∈ 𝑉))
4	3	eqcoms 2770	. . . . . . . . . . . 12 ⊢ (𝑋 = 𝑎 → (𝑎 ∈ 𝑉 ↔ 𝑋 ∈ 𝑉))
5		eleq1 2850	. . . . . . . . . . . . 13 ⊢ (𝑏 = 𝑌 → (𝑏 ∈ 𝑉 ↔ 𝑌 ∈ 𝑉))
6	5	eqcoms 2770	. . . . . . . . . . . 12 ⊢ (𝑌 = 𝑏 → (𝑏 ∈ 𝑉 ↔ 𝑌 ∈ 𝑉))
7	4, 6	bi2anan9 650	. . . . . . . . . . 11 ⊢ ((𝑋 = 𝑎 ∧ 𝑌 = 𝑏) → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) ↔ (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
8	7	biimpd 232	. . . . . . . . . 10 ⊢ ((𝑋 = 𝑎 ∧ 𝑌 = 𝑏) → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
9		eleq1 2850	. . . . . . . . . . . . . 14 ⊢ (𝑏 = 𝑋 → (𝑏 ∈ 𝑉 ↔ 𝑋 ∈ 𝑉))
10	9	eqcoms 2770	. . . . . . . . . . . . 13 ⊢ (𝑋 = 𝑏 → (𝑏 ∈ 𝑉 ↔ 𝑋 ∈ 𝑉))
11		eleq1 2850	. . . . . . . . . . . . . 14 ⊢ (𝑎 = 𝑌 → (𝑎 ∈ 𝑉 ↔ 𝑌 ∈ 𝑉))
12	11	eqcoms 2770	. . . . . . . . . . . . 13 ⊢ (𝑌 = 𝑎 → (𝑎 ∈ 𝑉 ↔ 𝑌 ∈ 𝑉))
13	10, 12	bi2anan9 650	. . . . . . . . . . . 12 ⊢ ((𝑋 = 𝑏 ∧ 𝑌 = 𝑎) → ((𝑏 ∈ 𝑉 ∧ 𝑎 ∈ 𝑉) ↔ (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
14	13	biimpd 232	. . . . . . . . . . 11 ⊢ ((𝑋 = 𝑏 ∧ 𝑌 = 𝑎) → ((𝑏 ∈ 𝑉 ∧ 𝑎 ∈ 𝑉) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
15	14	ancomsd 471	. . . . . . . . . 10 ⊢ ((𝑋 = 𝑏 ∧ 𝑌 = 𝑎) → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
16	8, 15	jaoi 871	. . . . . . . . 9 ⊢ (((𝑋 = 𝑎 ∧ 𝑌 = 𝑏) ∨ (𝑋 = 𝑏 ∧ 𝑌 = 𝑎)) → ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
17	16	com12 33	. . . . . . . 8 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → (((𝑋 = 𝑎 ∧ 𝑌 = 𝑏) ∨ (𝑋 = 𝑏 ∧ 𝑌 = 𝑎)) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
18	17	adantl 487	. . . . . . 7 ⊢ (((𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → (((𝑋 = 𝑎 ∧ 𝑌 = 𝑏) ∨ (𝑋 = 𝑏 ∧ 𝑌 = 𝑎)) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
19	2, 18	sylbid 243	. . . . . 6 ⊢ (((𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊) ∧ (𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉)) → ({𝑋, 𝑌} = {𝑎, 𝑏} → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
20	19	expcom 419	. . . . 5 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → ((𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊) → ({𝑋, 𝑌} = {𝑎, 𝑏} → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉))))
21	20	com23 87	. . . 4 ⊢ ((𝑎 ∈ 𝑉 ∧ 𝑏 ∈ 𝑉) → ({𝑋, 𝑌} = {𝑎, 𝑏} → ((𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉))))
22	21	rexlimivv 3206	. . 3 ⊢ (∃𝑎 ∈ 𝑉 ∃𝑏 ∈ 𝑉 {𝑋, 𝑌} = {𝑎, 𝑏} → ((𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
23	1, 22	syl 18	. 2 ⊢ ({𝑋, 𝑌} ∈ (Pairs‘𝑉) → ((𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉)))
24	23	imp 412	1 ⊢ (({𝑋, 𝑌} ∈ (Pairs‘𝑉) ∧ (𝑋 ∈ 𝑈 ∧ 𝑌 ∈ 𝑊)) → (𝑋 ∈ 𝑉 ∧ 𝑌 ∈ 𝑉))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   ∨ wo 861   = wceq 1570   ∈ wcel 2145  ∃wrex 3088  {cpr 4589  ‘cfv 6537  Pairscspr 48385

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2734  ax-rep 5236  ax-sep 5255  ax-nul 5267  ax-pr 5402  ax-un 7740

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rab 3415  df-v 3455  df-sbc 3743  df-csb 3851  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-nul 4283  df-if 4486  df-pw 4562  df-sn 4588  df-pr 4590  df-op 4594  df-uni 4871  df-iun 4956  df-br 5108  df-opab 5172  df-mpt 5191  df-id 5554  df-xp 5665  df-rel 5666  df-cnv 5667  df-co 5668  df-dm 5669  df-iota 6493  df-fun 6539  df-fv 6545  df-spr 48386

This theorem is used by:  prsssprel  48396  sprsymrelfolem2  48401