Theorem opeluu 4182

Description: Each member of an ordered pair belongs to the union of the union of a class to which the ordered pair belongs. Lemma 3D of [Enderton] p. 41. (Contributed by NM, 31-Mar-1995.) (Revised by Mario Carneiro, 27-Feb-2016.)

Hypotheses

Ref	Expression
opeluu.1	⊢ 𝐴 ∈ V
opeluu.2	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
opeluu	⊢ (⟨𝐴, 𝐵⟩ ∈ 𝐶 → (𝐴 ∈ ∪ ∪ 𝐶 ∧ 𝐵 ∈ ∪ ∪ 𝐶))

Proof of Theorem opeluu

Step	Hyp	Ref	Expression
1		opeluu.1	. . . 4 ⊢ 𝐴 ∈ V
2	1	prid1 3476	. . 3 ⊢ 𝐴 ∈ {𝐴, 𝐵}
3		opeluu.2	. . . . 5 ⊢ 𝐵 ∈ V
4	1, 3	opi2 3970	. . . 4 ⊢ {𝐴, 𝐵} ∈ ⟨𝐴, 𝐵⟩
5		elunii 3585	. . . 4 ⊢ (({𝐴, 𝐵} ∈ ⟨𝐴, 𝐵⟩ ∧ ⟨𝐴, 𝐵⟩ ∈ 𝐶) → {𝐴, 𝐵} ∈ ∪ 𝐶)
6	4, 5	mpan 400	. . 3 ⊢ (⟨𝐴, 𝐵⟩ ∈ 𝐶 → {𝐴, 𝐵} ∈ ∪ 𝐶)
7		elunii 3585	. . 3 ⊢ ((𝐴 ∈ {𝐴, 𝐵} ∧ {𝐴, 𝐵} ∈ ∪ 𝐶) → 𝐴 ∈ ∪ ∪ 𝐶)
8	2, 6, 7	sylancr 393	. 2 ⊢ (⟨𝐴, 𝐵⟩ ∈ 𝐶 → 𝐴 ∈ ∪ ∪ 𝐶)
9	3	prid2 3477	. . 3 ⊢ 𝐵 ∈ {𝐴, 𝐵}
10		elunii 3585	. . 3 ⊢ ((𝐵 ∈ {𝐴, 𝐵} ∧ {𝐴, 𝐵} ∈ ∪ 𝐶) → 𝐵 ∈ ∪ ∪ 𝐶)
11	9, 6, 10	sylancr 393	. 2 ⊢ (⟨𝐴, 𝐵⟩ ∈ 𝐶 → 𝐵 ∈ ∪ ∪ 𝐶)
12	8, 11	jca 290	1 ⊢ (⟨𝐴, 𝐵⟩ ∈ 𝐶 → (𝐴 ∈ ∪ ∪ 𝐶 ∧ 𝐵 ∈ ∪ ∪ 𝐶))

Syntax hints:   → wi 4   ∧ wa 97   ∈ wcel 1393  Vcvv 2557  {cpr 3376  ⟨cop 3378  ∪ cuni 3580

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-14 1405  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022  ax-sep 3875  ax-pr 3944

This theorem depends on definitions:  df-bi 110  df-3an 887  df-tru 1246  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-v 2559  df-un 2922  df-sn 3381  df-pr 3382  df-op 3384  df-uni 3581

This theorem is referenced by:  asymref  4710