Theorem dfrel4 6219

Description: A relation can be expressed as the set of ordered pairs in it. An analogue of dffn5 6974 for relations. (Contributed by Mario Carneiro, 16-Aug-2015.) (Revised by Thierry Arnoux, 11-May-2017.)

Hypotheses

Ref	Expression
dfrel4.1	⊢ Ⅎ𝑥𝑅
dfrel4.2	⊢ Ⅎ𝑦𝑅

Assertion

Ref	Expression
dfrel4	⊢ (Rel 𝑅 ↔ 𝑅 = {⟨𝑥, 𝑦⟩ ∣ 𝑥𝑅𝑦})

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝑅(𝑥,𝑦)

Proof of Theorem dfrel4

Dummy variables 𝑎 𝑏 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		dfrel4v 6218	. 2 ⊢ (Rel 𝑅 ↔ 𝑅 = {⟨𝑎, 𝑏⟩ ∣ 𝑎𝑅𝑏})
2		nfcv 2905	. . . . 5 ⊢ Ⅎ𝑥𝑎
3		dfrel4.1	. . . . 5 ⊢ Ⅎ𝑥𝑅
4		nfcv 2905	. . . . 5 ⊢ Ⅎ𝑥𝑏
5	2, 3, 4	nfbr 5198	. . . 4 ⊢ Ⅎ𝑥 𝑎𝑅𝑏
6		nfcv 2905	. . . . 5 ⊢ Ⅎ𝑦𝑎
7		dfrel4.2	. . . . 5 ⊢ Ⅎ𝑦𝑅
8		nfcv 2905	. . . . 5 ⊢ Ⅎ𝑦𝑏
9	6, 7, 8	nfbr 5198	. . . 4 ⊢ Ⅎ𝑦 𝑎𝑅𝑏
10		nfv 1914	. . . 4 ⊢ Ⅎ𝑎 𝑥𝑅𝑦
11		nfv 1914	. . . 4 ⊢ Ⅎ𝑏 𝑥𝑅𝑦
12		breq12 5156	. . . 4 ⊢ ((𝑎 = 𝑥 ∧ 𝑏 = 𝑦) → (𝑎𝑅𝑏 ↔ 𝑥𝑅𝑦))
13	5, 9, 10, 11, 12	cbvopab 5223	. . 3 ⊢ {⟨𝑎, 𝑏⟩ ∣ 𝑎𝑅𝑏} = {⟨𝑥, 𝑦⟩ ∣ 𝑥𝑅𝑦}
14	13	eqeq2i 2750	. 2 ⊢ (𝑅 = {⟨𝑎, 𝑏⟩ ∣ 𝑎𝑅𝑏} ↔ 𝑅 = {⟨𝑥, 𝑦⟩ ∣ 𝑥𝑅𝑦})
15	1, 14	bitri 275	1 ⊢ (Rel 𝑅 ↔ 𝑅 = {⟨𝑥, 𝑦⟩ ∣ 𝑥𝑅𝑦})

Syntax hints:   ↔ wb 206   = wceq 1539  Ⅎwnfc 2890   class class class wbr 5151  {copab 5213  Rel wrel 5698

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1794  ax-4 1808  ax-5 1910  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-10 2141  ax-11 2157  ax-12 2177  ax-ext 2708  ax-sep 5305  ax-nul 5315  ax-pr 5441

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1542  df-fal 1552  df-ex 1779  df-nf 1783  df-sb 2065  df-clab 2715  df-cleq 2729  df-clel 2816  df-nfc 2892  df-rab 3437  df-v 3483  df-dif 3969  df-un 3971  df-ss 3983  df-nul 4343  df-if 4535  df-sn 4635  df-pr 4637  df-op 4641  df-br 5152  df-opab 5214  df-xp 5699  df-rel 5700  df-cnv 5701

This theorem is referenced by:  feqmptdf  6986