Theorem triin 5231

Description: An indexed intersection of a class of transitive sets is transitive. (Contributed by BJ, 3-Oct-2022.)

Assertion

Ref	Expression
triin	⊢ (∀𝑥 ∈ 𝐴 Tr 𝐵 → Tr ∩ 𝑥 ∈ 𝐴 𝐵)

Proof of Theorem triin

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		eliin 4960	. . . . 5 ⊢ (𝑦 ∈ V → (𝑦 ∈ ∩ 𝑥 ∈ 𝐴 𝐵 ↔ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵))
2	1	elv 3452	. . . 4 ⊢ (𝑦 ∈ ∩ 𝑥 ∈ 𝐴 𝐵 ↔ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵)
3		r19.26 3091	. . . . . 6 ⊢ (∀𝑥 ∈ 𝐴 (Tr 𝐵 ∧ 𝑦 ∈ 𝐵) ↔ (∀𝑥 ∈ 𝐴 Tr 𝐵 ∧ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵))
4		trss 5225	. . . . . . . 8 ⊢ (Tr 𝐵 → (𝑦 ∈ 𝐵 → 𝑦 ⊆ 𝐵))
5	4	imp 406	. . . . . . 7 ⊢ ((Tr 𝐵 ∧ 𝑦 ∈ 𝐵) → 𝑦 ⊆ 𝐵)
6	5	ralimi 3066	. . . . . 6 ⊢ (∀𝑥 ∈ 𝐴 (Tr 𝐵 ∧ 𝑦 ∈ 𝐵) → ∀𝑥 ∈ 𝐴 𝑦 ⊆ 𝐵)
7	3, 6	sylbir 235	. . . . 5 ⊢ ((∀𝑥 ∈ 𝐴 Tr 𝐵 ∧ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵) → ∀𝑥 ∈ 𝐴 𝑦 ⊆ 𝐵)
8		ssiin 5019	. . . . 5 ⊢ (𝑦 ⊆ ∩ 𝑥 ∈ 𝐴 𝐵 ↔ ∀𝑥 ∈ 𝐴 𝑦 ⊆ 𝐵)
9	7, 8	sylibr 234	. . . 4 ⊢ ((∀𝑥 ∈ 𝐴 Tr 𝐵 ∧ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵) → 𝑦 ⊆ ∩ 𝑥 ∈ 𝐴 𝐵)
10	2, 9	sylan2b 594	. . 3 ⊢ ((∀𝑥 ∈ 𝐴 Tr 𝐵 ∧ 𝑦 ∈ ∩ 𝑥 ∈ 𝐴 𝐵) → 𝑦 ⊆ ∩ 𝑥 ∈ 𝐴 𝐵)
11	10	ralrimiva 3125	. 2 ⊢ (∀𝑥 ∈ 𝐴 Tr 𝐵 → ∀𝑦 ∈ ∩ 𝑥 ∈ 𝐴 𝐵𝑦 ⊆ ∩ 𝑥 ∈ 𝐴 𝐵)
12		dftr3 5220	. 2 ⊢ (Tr ∩ 𝑥 ∈ 𝐴 𝐵 ↔ ∀𝑦 ∈ ∩ 𝑥 ∈ 𝐴 𝐵𝑦 ⊆ ∩ 𝑥 ∈ 𝐴 𝐵)
13	11, 12	sylibr 234	1 ⊢ (∀𝑥 ∈ 𝐴 Tr 𝐵 → Tr ∩ 𝑥 ∈ 𝐴 𝐵)

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   ∈ wcel 2109  ∀wral 3044  Vcvv 3447   ⊆ wss 3914  ∩ ciin 4956  Tr wtr 5214

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-11 2158  ax-12 2178  ax-ext 2701

This theorem depends on definitions:  df-bi 207  df-an 396  df-tru 1543  df-ex 1780  df-nf 1784  df-sb 2066  df-clab 2708  df-cleq 2721  df-clel 2803  df-nfc 2878  df-ral 3045  df-v 3449  df-ss 3931  df-uni 4872  df-iin 4958  df-tr 5215

This theorem is referenced by:  trint  5232