Theorem axprlem3OLD 5398

Description: Obsolete version of axprlem3 5394 as of 18-Sep-2025. (Contributed by Rohan Ridenour, 10-Aug-2023.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
axprlem3OLD	⊢ ∃𝑧∀𝑤(𝑤 ∈ 𝑧 ↔ ∃𝑠(𝑠 ∈ 𝑝 ∧ if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦)))

Distinct variable groups:   𝑥,𝑧,𝑤   𝑦,𝑧,𝑤   𝑧,𝑛,𝑤   𝑧,𝑠,𝑝,𝑤

Proof of Theorem axprlem3OLD

Step	Hyp	Ref	Expression
1		nfv 1947	. . 3 ⊢ Ⅎ𝑧if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦)
2	1	axrep4 5242	. 2 ⊢ (∀𝑠∃𝑧∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧) → ∃𝑧∀𝑤(𝑤 ∈ 𝑧 ↔ ∃𝑠(𝑠 ∈ 𝑝 ∧ if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦))))
3		ax6evr 2048	. . . 4 ⊢ ∃𝑧 𝑥 = 𝑧
4		ifptru 1091	. . . . . . . . 9 ⊢ (∃𝑛 𝑛 ∈ 𝑠 → (if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) ↔ 𝑤 = 𝑥))
5	4	biimpd 232	. . . . . . . 8 ⊢ (∃𝑛 𝑛 ∈ 𝑠 → (if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑥))
6		equtrr 2055	. . . . . . . 8 ⊢ (𝑥 = 𝑧 → (𝑤 = 𝑥 → 𝑤 = 𝑧))
7	5, 6	sylan9r 518	. . . . . . 7 ⊢ ((𝑥 = 𝑧 ∧ ∃𝑛 𝑛 ∈ 𝑠) → (if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧))
8	7	alrimiv 1960	. . . . . 6 ⊢ ((𝑥 = 𝑧 ∧ ∃𝑛 𝑛 ∈ 𝑠) → ∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧))
9	8	expcom 419	. . . . 5 ⊢ (∃𝑛 𝑛 ∈ 𝑠 → (𝑥 = 𝑧 → ∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧)))
10	9	eximdv 1950	. . . 4 ⊢ (∃𝑛 𝑛 ∈ 𝑠 → (∃𝑧 𝑥 = 𝑧 → ∃𝑧∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧)))
11	3, 10	mpi 21	. . 3 ⊢ (∃𝑛 𝑛 ∈ 𝑠 → ∃𝑧∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧))
12		ax6evr 2048	. . . 4 ⊢ ∃𝑧 𝑦 = 𝑧
13		ifpfal 1092	. . . . . . . . . 10 ⊢ (¬ ∃𝑛 𝑛 ∈ 𝑠 → (if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) ↔ 𝑤 = 𝑦))
14	13	biimpd 232	. . . . . . . . 9 ⊢ (¬ ∃𝑛 𝑛 ∈ 𝑠 → (if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑦))
15	14	adantl 487	. . . . . . . 8 ⊢ ((𝑦 = 𝑧 ∧ ¬ ∃𝑛 𝑛 ∈ 𝑠) → (if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑦))
16		simpl 488	. . . . . . . 8 ⊢ ((𝑦 = 𝑧 ∧ ¬ ∃𝑛 𝑛 ∈ 𝑠) → 𝑦 = 𝑧)
17		equtr 2054	. . . . . . . 8 ⊢ (𝑤 = 𝑦 → (𝑦 = 𝑧 → 𝑤 = 𝑧))
18	15, 16, 17	syl6ci 72	. . . . . . 7 ⊢ ((𝑦 = 𝑧 ∧ ¬ ∃𝑛 𝑛 ∈ 𝑠) → (if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧))
19	18	alrimiv 1960	. . . . . 6 ⊢ ((𝑦 = 𝑧 ∧ ¬ ∃𝑛 𝑛 ∈ 𝑠) → ∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧))
20	19	expcom 419	. . . . 5 ⊢ (¬ ∃𝑛 𝑛 ∈ 𝑠 → (𝑦 = 𝑧 → ∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧)))
21	20	eximdv 1950	. . . 4 ⊢ (¬ ∃𝑛 𝑛 ∈ 𝑠 → (∃𝑧 𝑦 = 𝑧 → ∃𝑧∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧)))
22	12, 21	mpi 21	. . 3 ⊢ (¬ ∃𝑛 𝑛 ∈ 𝑠 → ∃𝑧∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧))
23	11, 22	pm2.61i 184	. 2 ⊢ ∃𝑧∀𝑤(if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦) → 𝑤 = 𝑧)
24	2, 23	mpg 1830	1 ⊢ ∃𝑧∀𝑤(𝑤 ∈ 𝑧 ↔ ∃𝑠(𝑠 ∈ 𝑝 ∧ if-(∃𝑛 𝑛 ∈ 𝑠, 𝑤 = 𝑥, 𝑤 = 𝑦)))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∧ wa 401  if-wif 1078  ∀wal 1568  ∃wex 1812   ∈ wcel 2145

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-12 2215  ax-rep 5236

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-ifp 1079  df-ex 1813  df-nf 1817

This theorem is used by:  axprOLD  5401