Theorem ss2iundv 42969

Description: Subclass theorem for indexed union. (Contributed by RP, 17-Jul-2020.)

Hypotheses

Ref	Expression
ss2iundv.el	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝑌 ∈ 𝐶)
ss2iundv.sub	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴 ∧ 𝑦 = 𝑌) → 𝐷 = 𝐺)
ss2iundv.ss	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ⊆ 𝐺)

Assertion

Ref	Expression
ss2iundv	⊢ (𝜑 → ∪ 𝑥 ∈ 𝐴 𝐵 ⊆ ∪ 𝑦 ∈ 𝐶 𝐷)

Distinct variable groups:   𝑥,𝑦,𝜑   𝑦,𝐴   𝑦,𝐵   𝑥,𝐶,𝑦   𝑥,𝐷   𝑦,𝐺   𝑦,𝑌

Allowed substitution hints:   𝐴(𝑥)   𝐵(𝑥)   𝐷(𝑦)   𝐺(𝑥)   𝑌(𝑥)

Proof of Theorem ss2iundv

Step	Hyp	Ref	Expression
1		nfv 1909	. 2 ⊢ Ⅎ𝑥𝜑
2		nfv 1909	. 2 ⊢ Ⅎ𝑦𝜑
3		nfcv 2897	. 2 ⊢ Ⅎ𝑦𝑌
4		nfcv 2897	. 2 ⊢ Ⅎ𝑦𝐴
5		nfcv 2897	. 2 ⊢ Ⅎ𝑦𝐵
6		nfcv 2897	. 2 ⊢ Ⅎ𝑥𝐶
7		nfcv 2897	. 2 ⊢ Ⅎ𝑦𝐶
8		nfcv 2897	. 2 ⊢ Ⅎ𝑥𝐷
9		nfcv 2897	. 2 ⊢ Ⅎ𝑦𝐺
10		ss2iundv.el	. 2 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝑌 ∈ 𝐶)
11		ss2iundv.sub	. 2 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴 ∧ 𝑦 = 𝑌) → 𝐷 = 𝐺)
12		ss2iundv.ss	. 2 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝐵 ⊆ 𝐺)
13	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12	ss2iundf 42968	1 ⊢ (𝜑 → ∪ 𝑥 ∈ 𝐴 𝐵 ⊆ ∪ 𝑦 ∈ 𝐶 𝐷)

Syntax hints:   → wi 4   ∧ wa 395   ∧ w3a 1084   = wceq 1533   ∈ wcel 2098   ⊆ wss 3943  ∪ ciun 4990

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1905  ax-6 1963  ax-7 2003  ax-8 2100  ax-9 2108  ax-10 2129  ax-11 2146  ax-12 2163  ax-ext 2697

This theorem depends on definitions:  df-bi 206  df-an 396  df-or 845  df-3an 1086  df-tru 1536  df-ex 1774  df-nf 1778  df-sb 2060  df-clab 2704  df-cleq 2718  df-clel 2804  df-nfc 2879  df-ral 3056  df-rex 3065  df-v 3470  df-in 3950  df-ss 3960  df-iun 4992

This theorem is referenced by: (None)