Theorem frrlem5c 31770

Description: Lemma for founded recursion. The union of a subclass of 𝐵 is a function. (Contributed by Paul Chapman, 29-Apr-2012.)

Hypotheses

Ref	Expression
frrlem5.1	⊢ 𝑅 Fr 𝐴
frrlem5.2	⊢ 𝑅 Se 𝐴
frrlem5.3	⊢ 𝐵 = {𝑓 ∣ ∃𝑥(𝑓 Fn 𝑥 ∧ (𝑥 ⊆ 𝐴 ∧ ∀𝑦 ∈ 𝑥 Pred(𝑅, 𝐴, 𝑦) ⊆ 𝑥 ∧ ∀𝑦 ∈ 𝑥 (𝑓‘𝑦) = (𝑦𝐺(𝑓 ↾ Pred(𝑅, 𝐴, 𝑦)))))}

Assertion

Ref	Expression
frrlem5c	⊢ (𝐶 ⊆ 𝐵 → Fun ∪ 𝐶)

Distinct variable groups:   𝐴,𝑓,𝑥,𝑦   𝑓,𝐺,𝑥,𝑦   𝑅,𝑓,𝑥,𝑦   𝑥,𝐵

Allowed substitution hints:   𝐵(𝑦,𝑓)   𝐶(𝑥,𝑦,𝑓)

Proof of Theorem frrlem5c

Dummy variables 𝑔 ℎ 𝑢 𝑣 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		uniss 4456	. 2 ⊢ (𝐶 ⊆ 𝐵 → ∪ 𝐶 ⊆ ∪ 𝐵)
2		ssid 3622	. . . 4 ⊢ 𝐵 ⊆ 𝐵
3		frrlem5.1	. . . . 5 ⊢ 𝑅 Fr 𝐴
4		frrlem5.2	. . . . 5 ⊢ 𝑅 Se 𝐴
5		frrlem5.3	. . . . 5 ⊢ 𝐵 = {𝑓 ∣ ∃𝑥(𝑓 Fn 𝑥 ∧ (𝑥 ⊆ 𝐴 ∧ ∀𝑦 ∈ 𝑥 Pred(𝑅, 𝐴, 𝑦) ⊆ 𝑥 ∧ ∀𝑦 ∈ 𝑥 (𝑓‘𝑦) = (𝑦𝐺(𝑓 ↾ Pred(𝑅, 𝐴, 𝑦)))))}
6	3, 4, 5	frrlem5b 31769	. . . 4 ⊢ (𝐵 ⊆ 𝐵 → Rel ∪ 𝐵)
7	2, 6	ax-mp 5	. . 3 ⊢ Rel ∪ 𝐵
8		eluni 4437	. . . . . . . . 9 ⊢ (⟨𝑥, 𝑢⟩ ∈ ∪ 𝐵 ↔ ∃𝑔(⟨𝑥, 𝑢⟩ ∈ 𝑔 ∧ 𝑔 ∈ 𝐵))
9		df-br 4652	. . . . . . . . 9 ⊢ (𝑥∪ 𝐵𝑢 ↔ ⟨𝑥, 𝑢⟩ ∈ ∪ 𝐵)
10		df-br 4652	. . . . . . . . . . 11 ⊢ (𝑥𝑔𝑢 ↔ ⟨𝑥, 𝑢⟩ ∈ 𝑔)
11	10	anbi1i 731	. . . . . . . . . 10 ⊢ ((𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ↔ (⟨𝑥, 𝑢⟩ ∈ 𝑔 ∧ 𝑔 ∈ 𝐵))
12	11	exbii 1773	. . . . . . . . 9 ⊢ (∃𝑔(𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ↔ ∃𝑔(⟨𝑥, 𝑢⟩ ∈ 𝑔 ∧ 𝑔 ∈ 𝐵))
13	8, 9, 12	3bitr4i 292	. . . . . . . 8 ⊢ (𝑥∪ 𝐵𝑢 ↔ ∃𝑔(𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵))
14		eluni 4437	. . . . . . . . 9 ⊢ (⟨𝑥, 𝑣⟩ ∈ ∪ 𝐵 ↔ ∃ℎ(⟨𝑥, 𝑣⟩ ∈ ℎ ∧ ℎ ∈ 𝐵))
15		df-br 4652	. . . . . . . . 9 ⊢ (𝑥∪ 𝐵𝑣 ↔ ⟨𝑥, 𝑣⟩ ∈ ∪ 𝐵)
16		df-br 4652	. . . . . . . . . . 11 ⊢ (𝑥ℎ𝑣 ↔ ⟨𝑥, 𝑣⟩ ∈ ℎ)
17	16	anbi1i 731	. . . . . . . . . 10 ⊢ ((𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵) ↔ (⟨𝑥, 𝑣⟩ ∈ ℎ ∧ ℎ ∈ 𝐵))
18	17	exbii 1773	. . . . . . . . 9 ⊢ (∃ℎ(𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵) ↔ ∃ℎ(⟨𝑥, 𝑣⟩ ∈ ℎ ∧ ℎ ∈ 𝐵))
19	14, 15, 18	3bitr4i 292	. . . . . . . 8 ⊢ (𝑥∪ 𝐵𝑣 ↔ ∃ℎ(𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵))
20	13, 19	anbi12i 733	. . . . . . 7 ⊢ ((𝑥∪ 𝐵𝑢 ∧ 𝑥∪ 𝐵𝑣) ↔ (∃𝑔(𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ∧ ∃ℎ(𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵)))
21		eeanv 2181	. . . . . . 7 ⊢ (∃𝑔∃ℎ((𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ∧ (𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵)) ↔ (∃𝑔(𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ∧ ∃ℎ(𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵)))
22	20, 21	bitr4i 267	. . . . . 6 ⊢ ((𝑥∪ 𝐵𝑢 ∧ 𝑥∪ 𝐵𝑣) ↔ ∃𝑔∃ℎ((𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ∧ (𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵)))
23	3, 4, 5	frrlem5 31768	. . . . . . . . 9 ⊢ ((𝑔 ∈ 𝐵 ∧ ℎ ∈ 𝐵) → ((𝑥𝑔𝑢 ∧ 𝑥ℎ𝑣) → 𝑢 = 𝑣))
24	23	impcom 446	. . . . . . . 8 ⊢ (((𝑥𝑔𝑢 ∧ 𝑥ℎ𝑣) ∧ (𝑔 ∈ 𝐵 ∧ ℎ ∈ 𝐵)) → 𝑢 = 𝑣)
25	24	an4s 869	. . . . . . 7 ⊢ (((𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ∧ (𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵)) → 𝑢 = 𝑣)
26	25	exlimivv 1859	. . . . . 6 ⊢ (∃𝑔∃ℎ((𝑥𝑔𝑢 ∧ 𝑔 ∈ 𝐵) ∧ (𝑥ℎ𝑣 ∧ ℎ ∈ 𝐵)) → 𝑢 = 𝑣)
27	22, 26	sylbi 207	. . . . 5 ⊢ ((𝑥∪ 𝐵𝑢 ∧ 𝑥∪ 𝐵𝑣) → 𝑢 = 𝑣)
28	27	ax-gen 1721	. . . 4 ⊢ ∀𝑣((𝑥∪ 𝐵𝑢 ∧ 𝑥∪ 𝐵𝑣) → 𝑢 = 𝑣)
29	28	gen2 1722	. . 3 ⊢ ∀𝑥∀𝑢∀𝑣((𝑥∪ 𝐵𝑢 ∧ 𝑥∪ 𝐵𝑣) → 𝑢 = 𝑣)
30		dffun2 5896	. . 3 ⊢ (Fun ∪ 𝐵 ↔ (Rel ∪ 𝐵 ∧ ∀𝑥∀𝑢∀𝑣((𝑥∪ 𝐵𝑢 ∧ 𝑥∪ 𝐵𝑣) → 𝑢 = 𝑣)))
31	7, 29, 30	mpbir2an 955	. 2 ⊢ Fun ∪ 𝐵
32		funss 5905	. 2 ⊢ (∪ 𝐶 ⊆ ∪ 𝐵 → (Fun ∪ 𝐵 → Fun ∪ 𝐶))
33	1, 31, 32	mpisyl 21	1 ⊢ (𝐶 ⊆ 𝐵 → Fun ∪ 𝐶)

Syntax hints:   → wi 4   ∧ wa 384   ∧ w3a 1037  ∀wal 1480   = wceq 1482  ∃wex 1703   ∈ wcel 1989  {cab 2607  ∀wral 2911   ⊆ wss 3572  ⟨cop 4181  ∪ cuni 4434   class class class wbr 4651   Fr wfr 5068   Se wse 5069   ↾ cres 5114  Rel wrel 5117  Predcpred 5677  Fun wfun 5880   Fn wfn 5881  ‘cfv 5886  (class class class)co 6647

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1721  ax-4 1736  ax-5 1838  ax-6 1887  ax-7 1934  ax-8 1991  ax-9 1998  ax-10 2018  ax-11 2033  ax-12 2046  ax-13 2245  ax-ext 2601  ax-rep 4769  ax-sep 4779  ax-nul 4787  ax-pow 4841  ax-pr 4904  ax-un 6946  ax-inf2 8535

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1485  df-ex 1704  df-nf 1709  df-sb 1880  df-eu 2473  df-mo 2474  df-clab 2608  df-cleq 2614  df-clel 2617  df-nfc 2752  df-ne 2794  df-ral 2916  df-rex 2917  df-reu 2918  df-rab 2920  df-v 3200  df-sbc 3434  df-csb 3532  df-dif 3575  df-un 3577  df-in 3579  df-ss 3586  df-pss 3588  df-nul 3914  df-if 4085  df-pw 4158  df-sn 4176  df-pr 4178  df-tp 4180  df-op 4182  df-uni 4435  df-iun 4520  df-br 4652  df-opab 4711  df-mpt 4728  df-tr 4751  df-id 5022  df-eprel 5027  df-po 5033  df-so 5034  df-fr 5071  df-se 5072  df-we 5073  df-xp 5118  df-rel 5119  df-cnv 5120  df-co 5121  df-dm 5122  df-rn 5123  df-res 5124  df-ima 5125  df-pred 5678  df-ord 5724  df-on 5725  df-lim 5726  df-suc 5727  df-iota 5849  df-fun 5888  df-fn 5889  df-f 5890  df-f1 5891  df-fo 5892  df-f1o 5893  df-fv 5894  df-ov 6650  df-om 7063  df-wrecs 7404  df-recs 7465  df-rdg 7503  df-trpred 31702

This theorem is referenced by:  frrlem10  31775