Theorem prtlem17 39464

Description: Lemma for prter2 39469. (Contributed by Rodolfo Medina, 15-Oct-2010.)

Assertion

Ref	Expression
prtlem17	⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥) → (∃𝑦 ∈ 𝐴 (𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦) → 𝑤 ∈ 𝑥)))

Distinct variable groups:   𝑥,𝑦,𝐴   𝑥,𝑧,𝑦   𝑦,𝑤

Allowed substitution hints:   𝐴(𝑧,𝑤)

Proof of Theorem prtlem17

Step	Hyp	Ref	Expression
1		df-rex 3086	. . 3 ⊢ (∃𝑦 ∈ 𝐴 (𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦) ↔ ∃𝑦(𝑦 ∈ 𝐴 ∧ (𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦)))
2		an32 656	. . . . . . . 8 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ 𝑧 ∈ 𝑥) ↔ ((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥) ∧ 𝑦 ∈ 𝐴))
3		prtlem14 39462	. . . . . . . . . . 11 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → ((𝑧 ∈ 𝑥 ∧ 𝑧 ∈ 𝑦) → 𝑥 = 𝑦)))
4		elequ2 2156	. . . . . . . . . . . 12 ⊢ (𝑥 = 𝑦 → (𝑤 ∈ 𝑥 ↔ 𝑤 ∈ 𝑦))
5	4	biimprd 250	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑦 → (𝑤 ∈ 𝑦 → 𝑤 ∈ 𝑥))
6	3, 5	syl8 76	. . . . . . . . . 10 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → ((𝑧 ∈ 𝑥 ∧ 𝑧 ∈ 𝑦) → (𝑤 ∈ 𝑦 → 𝑤 ∈ 𝑥))))
7	6	exp4a 435	. . . . . . . . 9 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → (𝑧 ∈ 𝑥 → (𝑧 ∈ 𝑦 → (𝑤 ∈ 𝑦 → 𝑤 ∈ 𝑥)))))
8	7	impd 414	. . . . . . . 8 ⊢ (Prt 𝐴 → (((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) ∧ 𝑧 ∈ 𝑥) → (𝑧 ∈ 𝑦 → (𝑤 ∈ 𝑦 → 𝑤 ∈ 𝑥))))
9	2, 8	biimtrrid 245	. . . . . . 7 ⊢ (Prt 𝐴 → (((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥) ∧ 𝑦 ∈ 𝐴) → (𝑧 ∈ 𝑦 → (𝑤 ∈ 𝑦 → 𝑤 ∈ 𝑥))))
10	9	expd 419	. . . . . 6 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥) → (𝑦 ∈ 𝐴 → (𝑧 ∈ 𝑦 → (𝑤 ∈ 𝑦 → 𝑤 ∈ 𝑥)))))
11	10	imp5a 444	. . . . 5 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥) → (𝑦 ∈ 𝐴 → ((𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦) → 𝑤 ∈ 𝑥))))
12	11	imp4b 425	. . . 4 ⊢ ((Prt 𝐴 ∧ (𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥)) → ((𝑦 ∈ 𝐴 ∧ (𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦)) → 𝑤 ∈ 𝑥))
13	12	exlimdv 1952	. . 3 ⊢ ((Prt 𝐴 ∧ (𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥)) → (∃𝑦(𝑦 ∈ 𝐴 ∧ (𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦)) → 𝑤 ∈ 𝑥))
14	1, 13	biimtrid 244	. 2 ⊢ ((Prt 𝐴 ∧ (𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥)) → (∃𝑦 ∈ 𝐴 (𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦) → 𝑤 ∈ 𝑥))
15	14	ex 416	1 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑧 ∈ 𝑥) → (∃𝑦 ∈ 𝐴 (𝑧 ∈ 𝑦 ∧ 𝑤 ∈ 𝑦) → 𝑤 ∈ 𝑥)))

Syntax hints:   → wi 4   ∧ wa 399  ∃wex 1798   ∈ wcel 2141  ∃wrex 3085  Prt wprt 39459

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1814  ax-4 1828  ax-5 1929  ax-6 1986  ax-7 2027  ax-8 2143  ax-9 2151  ax-12 2211  ax-ext 2733

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-tru 1562  df-fal 1572  df-ex 1799  df-sb 2090  df-clab 2740  df-cleq 2753  df-clel 2836  df-ral 3076  df-rex 3086  df-v 3455  df-dif 3907  df-in 3911  df-nul 4286  df-prt 39460

This theorem is referenced by:  prtlem18  39465