Theorem brcap 36517

Description: Binary relation form of the Cap function. (Contributed by Scott Fenton, 17-Apr-2014.) (Revised by Mario Carneiro, 19-Apr-2014.)

Hypotheses

Ref	Expression
brcap.1	⊢ 𝐴 ∈ V
brcap.2	⊢ 𝐵 ∈ V
brcap.3	⊢ 𝐶 ∈ V

Assertion

Ref	Expression
brcap	⊢ (⟨𝐴, 𝐵⟩Cap𝐶 ↔ 𝐶 = (𝐴 ∩ 𝐵))

Proof of Theorem brcap

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		opex 5439	. 2 ⊢ ⟨𝐴, 𝐵⟩ ∈ V
2		brcap.3	. 2 ⊢ 𝐶 ∈ V
3		df-cap 36447	. 2 ⊢ Cap = (((V × V) × V) ∖ ran ((V ⊗ E ) △ (((◡1st ∘ E ) ∩ (◡2nd ∘ E )) ⊗ V)))
4		brcap.1	. . . 4 ⊢ 𝐴 ∈ V
5		brcap.2	. . . 4 ⊢ 𝐵 ∈ V
6	4, 5	opelvv 5695	. . 3 ⊢ ⟨𝐴, 𝐵⟩ ∈ (V × V)
7		brxp 5704	. . 3 ⊢ (⟨𝐴, 𝐵⟩((V × V) × V)𝐶 ↔ (⟨𝐴, 𝐵⟩ ∈ (V × V) ∧ 𝐶 ∈ V))
8	6, 2, 7	mpbir2an 724	. 2 ⊢ ⟨𝐴, 𝐵⟩((V × V) × V)𝐶
9		epel 5558	. . . . . . 7 ⊢ (𝑥 E 𝑦 ↔ 𝑥 ∈ 𝑦)
10		vex 3454	. . . . . . . . 9 ⊢ 𝑦 ∈ V
11	10, 1	brcnv 5862	. . . . . . . 8 ⊢ (𝑦◡1st ⟨𝐴, 𝐵⟩ ↔ ⟨𝐴, 𝐵⟩1st 𝑦)
12	4, 5	br1steq 36350	. . . . . . . 8 ⊢ (⟨𝐴, 𝐵⟩1st 𝑦 ↔ 𝑦 = 𝐴)
13	11, 12	bitri 278	. . . . . . 7 ⊢ (𝑦◡1st ⟨𝐴, 𝐵⟩ ↔ 𝑦 = 𝐴)
14	9, 13	anbi12ci 641	. . . . . 6 ⊢ ((𝑥 E 𝑦 ∧ 𝑦◡1st ⟨𝐴, 𝐵⟩) ↔ (𝑦 = 𝐴 ∧ 𝑥 ∈ 𝑦))
15	14	exbii 1881	. . . . 5 ⊢ (∃𝑦(𝑥 E 𝑦 ∧ 𝑦◡1st ⟨𝐴, 𝐵⟩) ↔ ∃𝑦(𝑦 = 𝐴 ∧ 𝑥 ∈ 𝑦))
16		vex 3454	. . . . . 6 ⊢ 𝑥 ∈ V
17	16, 1	brco 5850	. . . . 5 ⊢ (𝑥(◡1st ∘ E )⟨𝐴, 𝐵⟩ ↔ ∃𝑦(𝑥 E 𝑦 ∧ 𝑦◡1st ⟨𝐴, 𝐵⟩))
18	4	clel3 3616	. . . . 5 ⊢ (𝑥 ∈ 𝐴 ↔ ∃𝑦(𝑦 = 𝐴 ∧ 𝑥 ∈ 𝑦))
19	15, 17, 18	3bitr4i 306	. . . 4 ⊢ (𝑥(◡1st ∘ E )⟨𝐴, 𝐵⟩ ↔ 𝑥 ∈ 𝐴)
20	10, 1	brcnv 5862	. . . . . . . 8 ⊢ (𝑦◡2nd ⟨𝐴, 𝐵⟩ ↔ ⟨𝐴, 𝐵⟩2nd 𝑦)
21	4, 5	br2ndeq 36351	. . . . . . . 8 ⊢ (⟨𝐴, 𝐵⟩2nd 𝑦 ↔ 𝑦 = 𝐵)
22	20, 21	bitri 278	. . . . . . 7 ⊢ (𝑦◡2nd ⟨𝐴, 𝐵⟩ ↔ 𝑦 = 𝐵)
23	9, 22	anbi12ci 641	. . . . . 6 ⊢ ((𝑥 E 𝑦 ∧ 𝑦◡2nd ⟨𝐴, 𝐵⟩) ↔ (𝑦 = 𝐵 ∧ 𝑥 ∈ 𝑦))
24	23	exbii 1881	. . . . 5 ⊢ (∃𝑦(𝑥 E 𝑦 ∧ 𝑦◡2nd ⟨𝐴, 𝐵⟩) ↔ ∃𝑦(𝑦 = 𝐵 ∧ 𝑥 ∈ 𝑦))
25	16, 1	brco 5850	. . . . 5 ⊢ (𝑥(◡2nd ∘ E )⟨𝐴, 𝐵⟩ ↔ ∃𝑦(𝑥 E 𝑦 ∧ 𝑦◡2nd ⟨𝐴, 𝐵⟩))
26	5	clel3 3616	. . . . 5 ⊢ (𝑥 ∈ 𝐵 ↔ ∃𝑦(𝑦 = 𝐵 ∧ 𝑥 ∈ 𝑦))
27	24, 25, 26	3bitr4i 306	. . . 4 ⊢ (𝑥(◡2nd ∘ E )⟨𝐴, 𝐵⟩ ↔ 𝑥 ∈ 𝐵)
28	19, 27	anbi12i 640	. . 3 ⊢ ((𝑥(◡1st ∘ E )⟨𝐴, 𝐵⟩ ∧ 𝑥(◡2nd ∘ E )⟨𝐴, 𝐵⟩) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵))
29		brin 5157	. . 3 ⊢ (𝑥((◡1st ∘ E ) ∩ (◡2nd ∘ E ))⟨𝐴, 𝐵⟩ ↔ (𝑥(◡1st ∘ E )⟨𝐴, 𝐵⟩ ∧ 𝑥(◡2nd ∘ E )⟨𝐴, 𝐵⟩))
30		elin 3915	. . 3 ⊢ (𝑥 ∈ (𝐴 ∩ 𝐵) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵))
31	28, 29, 30	3bitr4ri 307	. 2 ⊢ (𝑥 ∈ (𝐴 ∩ 𝐵) ↔ 𝑥((◡1st ∘ E ) ∩ (◡2nd ∘ E ))⟨𝐴, 𝐵⟩)
32	1, 2, 3, 8, 31	brtxpsd3 36473	1 ⊢ (⟨𝐴, 𝐵⟩Cap𝐶 ↔ 𝐶 = (𝐴 ∩ 𝐵))

This proof depends on syntax axioms:   ↔ wb 209   ∧ wa 401   = wceq 1570  ∃wex 1812   ∈ wcel 2145  Vcvv 3450   ∩ cin 3898  ⟨cop 4590   class class class wbr 5103   E cep 5554   × cxp 5653  ^◡ccnv 5654   ∘ ccom 5659  1^st c1st 7984  2^nd c2nd 7985  Capccap 36424

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-10 2178  ax-11 2194  ax-12 2213  ax-ext 2732  ax-sep 5251  ax-nul 5263  ax-pr 5398  ax-un 7736

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-ral 3077  df-rex 3087  df-rab 3413  df-v 3452  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-symdif 4199  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-opab 5168  df-mpt 5187  df-id 5550  df-eprel 5555  df-xp 5661  df-rel 5662  df-cnv 5663  df-co 5664  df-dm 5665  df-rn 5666  df-res 5667  df-iota 6489  df-fun 6535  df-fn 6536  df-f 6537  df-fo 6539  df-fv 6541  df-1st 7986  df-2nd 7987  df-txp 36431  df-cap 36447

This theorem is used by:  brrestrict  36528