Theorem cnvco 5832

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 1863	. . . 4 ⊢ (∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦) ↔ ∃𝑧(𝑧𝐴𝑦 ∧ 𝑥𝐵𝑧))
2		vex 3434	. . . . 5 ⊢ 𝑥 ∈ V
3		vex 3434	. . . . 5 ⊢ 𝑦 ∈ V
4	2, 3	brco 5817	. . . 4 ⊢ (𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
5		vex 3434	. . . . . . 7 ⊢ 𝑧 ∈ V
6	3, 5	brcnv 5829	. . . . . 6 ⊢ (𝑦◡𝐴𝑧 ↔ 𝑧𝐴𝑦)
7	5, 2	brcnv 5829	. . . . . 6 ⊢ (𝑧◡𝐵𝑥 ↔ 𝑥𝐵𝑧)
8	6, 7	anbi12i 629	. . . . 5 ⊢ ((𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥) ↔ (𝑧𝐴𝑦 ∧ 𝑥𝐵𝑧))
9	8	exbii 1850	. . . 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 5153	. 2 ⊢ {⟨𝑦, 𝑥⟩ ∣ 𝑥(𝐴 ∘ 𝐵)𝑦} = {⟨𝑦, 𝑥⟩ ∣ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥)}
12		df-cnv 5630	. 2 ⊢ ◡(𝐴 ∘ 𝐵) = {⟨𝑦, 𝑥⟩ ∣ 𝑥(𝐴 ∘ 𝐵)𝑦}
13		df-co 5631	. 2 ⊢ (◡𝐵 ∘ ◡𝐴) = {⟨𝑦, 𝑥⟩ ∣ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥)}
14	11, 12, 13	3eqtr4i 2770	1 ⊢ ◡(𝐴 ∘ 𝐵) = (◡𝐵 ∘ ◡𝐴)

Syntax hints:   ∧ wa 395   = wceq 1542  ∃wex 1781   class class class wbr 5086  {copab 5148  ^◡ccnv 5621   ∘ ccom 5626

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-ext 2709  ax-sep 5231  ax-pr 5368

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-sb 2069  df-clab 2716  df-cleq 2729  df-clel 2812  df-rab 3391  df-v 3432  df-dif 3893  df-un 3895  df-in 3897  df-ss 3907  df-nul 4275  df-if 4468  df-sn 4569  df-pr 4571  df-op 4575  df-br 5087  df-opab 5149  df-cnv 5630  df-co 5631

This theorem is referenced by:  rncoss  5924  rncoeq  5929  dmco  6211  cores2  6216  co01  6218  coi2  6220  relcnvtrg  6223  dfdm2  6237  f1cof1  6738  cofunex2g  7894  fparlem3  8055  fparlem4  8056  suppco  8147  fsuppcolem  9305  relexpcnv  14959  relexpaddg  14977  cnvps  18502  gimco  19201  gsumzf1o  19845  cnco  23209  ptrescn  23582  qtopcn  23657  hmeoco  23715  cncombf  25603  deg1val  26042  fcoinver  32663  ofpreima  32727  cycpmconjv  33208  cycpmconjs  33222  cyc3conja  33223  esplysply  33720  mbfmco  34414  eulerpartlemmf  34525  cvmliftmolem1  35469  cvmlift2lem9a  35491  cvmlift2lem9  35499  mclsppslem  35771  ftc1anclem3  38007  trlcocnv  41157  tendoicl  41233  cdlemk45  41384  rimco  42962  cononrel1  44024  cononrel2  44025  cnvtrcl0  44056  cnvtrrel  44100  relexpaddss  44148  frege131d  44194  brco2f1o  44462  brco3f1o  44463  clsneicnv  44535  neicvgnvo  44545  smfco  47234  upgrimpthslem1  48341  upgrimspths  48344