Theorem cnvco 5834

Description: Distributive law of converse over class composition. Theorem 26 of [Suppes] p. 64. (Contributed by NM, 19-Mar-1998.) (Proof shortened by Andrew Salmon, 27-Aug-2011.)

Assertion

Ref	Expression
cnvco	⊢ ◡(𝐴 ∘ 𝐵) = (◡𝐵 ∘ ◡𝐴)

Proof of Theorem cnvco

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

Step	Hyp	Ref	Expression
1		exancom 1862	. . . 4 ⊢ (∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ ∃𝑧(𝑧𝐴𝑦 ∧ 𝑥𝐵𝑧))
2		vex 3444	. . . . 5 ⊢ 𝑥 ∈ V
3		vex 3444	. . . . 5 ⊢ 𝑦 ∈ V
4	2, 3	brco 5819	. . . 4 ⊢ (𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
5		vex 3444	. . . . . . 7 ⊢ 𝑧 ∈ V
6	3, 5	brcnv 5831	. . . . . 6 ⊢ (𝑦◡𝐴𝑧 ↔ 𝑧𝐴𝑦)
7	5, 2	brcnv 5831	. . . . . 6 ⊢ (𝑧◡𝐵𝑥 ↔ 𝑥𝐵𝑧)
8	6, 7	anbi12i 628	. . . . 5 ⊢ ((𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥) ↔ (𝑧𝐴𝑦 ∧ 𝑥𝐵𝑧))
9	8	exbii 1849	. . . 4 ⊢ (∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥) ↔ ∃𝑧(𝑧𝐴𝑦 ∧ 𝑥𝐵𝑧))
10	1, 4, 9	3bitr4i 303	. . 3 ⊢ (𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥))
11	10	opabbii 5165	. 2 ⊢ {⟨𝑦, 𝑥⟩ ∣ 𝑥(𝐴 ∘ 𝐵)𝑦} = {⟨𝑦, 𝑥⟩ ∣ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥)}
12		df-cnv 5632	. 2 ⊢ ◡(𝐴 ∘ 𝐵) = {⟨𝑦, 𝑥⟩ ∣ 𝑥(𝐴 ∘ 𝐵)𝑦}
13		df-co 5633	. 2 ⊢ (◡𝐵 ∘ ◡𝐴) = {⟨𝑦, 𝑥⟩ ∣ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥)}
14	11, 12, 13	3eqtr4i 2769	1 ⊢ ◡(𝐴 ∘ 𝐵) = (◡𝐵 ∘ ◡𝐴)

Syntax hints:   ∧ wa 395   = wceq 1541  ∃wex 1780   class class class wbr 5098  {copab 5160  ^◡ccnv 5623   ∘ ccom 5628

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-ext 2708  ax-sep 5241  ax-nul 5251  ax-pr 5377

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-sb 2068  df-clab 2715  df-cleq 2728  df-clel 2811  df-rab 3400  df-v 3442  df-dif 3904  df-un 3906  df-ss 3918  df-nul 4286  df-if 4480  df-sn 4581  df-pr 4583  df-op 4587  df-br 5099  df-opab 5161  df-cnv 5632  df-co 5633

This theorem is referenced by:  rncoss  5926  rncoeq  5931  dmco  6213  cores2  6218  co01  6220  coi2  6222  relcnvtrg  6225  dfdm2  6239  f1cof1  6740  cofunex2g  7894  fparlem3  8056  fparlem4  8057  suppco  8148  fsuppcolem  9304  relexpcnv  14958  relexpaddg  14976  cnvps  18501  gimco  19197  gsumzf1o  19841  cnco  23210  ptrescn  23583  qtopcn  23658  hmeoco  23716  cncombf  25615  deg1val  26057  fcoinver  32679  ofpreima  32743  cycpmconjv  33224  cycpmconjs  33238  cyc3conja  33239  esplysply  33729  mbfmco  34421  eulerpartlemmf  34532  cvmliftmolem1  35475  cvmlift2lem9a  35497  cvmlift2lem9  35505  mclsppslem  35777  ftc1anclem3  37892  trlcocnv  40976  tendoicl  41052  cdlemk45  41203  rimco  42769  cononrel1  43831  cononrel2  43832  cnvtrcl0  43863  cnvtrrel  43907  relexpaddss  43955  frege131d  44001  brco2f1o  44269  brco3f1o  44270  clsneicnv  44342  neicvgnvo  44352  smfco  47042  upgrimpthslem1  48149  upgrimspths  48152