Theorem prtlem14 39899

Description: Lemma for prter1 39904, prter2 39906 and prtex 39905. (Contributed by Rodolfo Medina, 13-Oct-2010.)

Assertion

Ref	Expression
prtlem14	⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → ((𝑤 ∈ 𝑥 ∧ 𝑤 ∈ 𝑦) → 𝑥 = 𝑦)))

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

Allowed substitution hint:   𝐴(𝑤)

Proof of Theorem prtlem14

Step	Hyp	Ref	Expression
1		df-prt 39897	. . 3 ⊢ (Prt 𝐴 ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥 = 𝑦 ∨ (𝑥 ∩ 𝑦) = ∅))
2		rsp2 3280	. . 3 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥 = 𝑦 ∨ (𝑥 ∩ 𝑦) = ∅) → ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → (𝑥 = 𝑦 ∨ (𝑥 ∩ 𝑦) = ∅)))
3	1, 2	sylbi 220	. 2 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → (𝑥 = 𝑦 ∨ (𝑥 ∩ 𝑦) = ∅)))
4		elin 3915	. . . 4 ⊢ (𝑤 ∈ (𝑥 ∩ 𝑦) ↔ (𝑤 ∈ 𝑥 ∧ 𝑤 ∈ 𝑦))
5		eq0 4297	. . . . . 6 ⊢ ((𝑥 ∩ 𝑦) = ∅ ↔ ∀𝑤 ¬ 𝑤 ∈ (𝑥 ∩ 𝑦))
6		sp 2220	. . . . . 6 ⊢ (∀𝑤 ¬ 𝑤 ∈ (𝑥 ∩ 𝑦) → ¬ 𝑤 ∈ (𝑥 ∩ 𝑦))
7	5, 6	sylbi 220	. . . . 5 ⊢ ((𝑥 ∩ 𝑦) = ∅ → ¬ 𝑤 ∈ (𝑥 ∩ 𝑦))
8	7	pm2.21d 122	. . . 4 ⊢ ((𝑥 ∩ 𝑦) = ∅ → (𝑤 ∈ (𝑥 ∩ 𝑦) → 𝑥 = 𝑦))
9	4, 8	biimtrrid 246	. . 3 ⊢ ((𝑥 ∩ 𝑦) = ∅ → ((𝑤 ∈ 𝑥 ∧ 𝑤 ∈ 𝑦) → 𝑥 = 𝑦))
10	9	jao1i 872	. 2 ⊢ ((𝑥 = 𝑦 ∨ (𝑥 ∩ 𝑦) = ∅) → ((𝑤 ∈ 𝑥 ∧ 𝑤 ∈ 𝑦) → 𝑥 = 𝑦))
11	3, 10	syl6 36	1 ⊢ (Prt 𝐴 → ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐴) → ((𝑤 ∈ 𝑥 ∧ 𝑤 ∈ 𝑦) → 𝑥 = 𝑦)))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 401   ∨ wo 861  ∀wal 1568   = wceq 1570   ∈ wcel 2145  ∀wral 3077   ∩ cin 3898  ∅c0 4279  Prt wprt 39896

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-12 2213  ax-ext 2733

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-tru 1573  df-fal 1583  df-ex 1813  df-sb 2100  df-clab 2740  df-cleq 2753  df-clel 2836  df-ral 3078  df-v 3453  df-dif 3902  df-in 3906  df-nul 4280  df-prt 39897

This theorem is used by:  prtlem15  39900  prtlem17  39901