Theorem cnvco 5827

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 3445	. . . . 5 ⊢ 𝑥 ∈ V
3		vex 3445	. . . . 5 ⊢ 𝑦 ∈ V
4	2, 3	brco 5812	. . . 4 ⊢ (𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑧(𝑥𝐵𝑧 ∧ 𝑧𝐴𝑦))
5		vex 3445	. . . . . . 7 ⊢ 𝑧 ∈ V
6	3, 5	brcnv 5824	. . . . . 6 ⊢ (𝑦◡𝐴𝑧 ↔ 𝑧𝐴𝑦)
7	5, 2	brcnv 5824	. . . . . 6 ⊢ (𝑧◡𝐵𝑥 ↔ 𝑥𝐵𝑧)
8	6, 7	anbi12i 627	. . . . 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 302	. . 3 ⊢ (𝑥(𝐴 ∘ 𝐵)𝑦 ↔ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥))
11	10	opabbii 5159	. 2 ⊢ {⟨𝑦, 𝑥⟩ ∣ 𝑥(𝐴 ∘ 𝐵)𝑦} = {⟨𝑦, 𝑥⟩ ∣ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥)}
12		df-cnv 5628	. 2 ⊢ ◡(𝐴 ∘ 𝐵) = {⟨𝑦, 𝑥⟩ ∣ 𝑥(𝐴 ∘ 𝐵)𝑦}
13		df-co 5629	. 2 ⊢ (◡𝐵 ∘ ◡𝐴) = {⟨𝑦, 𝑥⟩ ∣ ∃𝑧(𝑦◡𝐴𝑧 ∧ 𝑧◡𝐵𝑥)}
14	11, 12, 13	3eqtr4i 2774	1 ⊢ ◡(𝐴 ∘ 𝐵) = (◡𝐵 ∘ ◡𝐴)

Syntax hints:   ∧ wa 396   = wceq 1540  ∃wex 1780   class class class wbr 5092  {copab 5154  ^◡ccnv 5619   ∘ ccom 5624

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 1912  ax-6 1970  ax-7 2010  ax-8 2107  ax-9 2115  ax-ext 2707  ax-sep 5243  ax-nul 5250  ax-pr 5372

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1781  df-sb 2067  df-clab 2714  df-cleq 2728  df-clel 2814  df-rab 3404  df-v 3443  df-dif 3901  df-un 3903  df-in 3905  df-ss 3915  df-nul 4270  df-if 4474  df-sn 4574  df-pr 4576  df-op 4580  df-br 5093  df-opab 5155  df-cnv 5628  df-co 5629

This theorem is referenced by:  rncoss  5913  rncoeq  5916  dmco  6192  cores2  6197  co01  6199  coi2  6201  relcnvtrg  6204  dfdm2  6219  f1cof1  6732  f1coOLD  6734  cofunex2g  7860  fparlem3  8022  fparlem4  8023  suppco  8092  fsuppcolem  9258  relexpcnv  14845  relexpaddg  14863  cnvps  18393  gimco  18980  gsumzf1o  19608  cnco  22523  ptrescn  22896  qtopcn  22971  hmeoco  23029  cncombf  24928  deg1val  25367  fcoinver  31233  ofpreima  31289  cycpmconjv  31696  cycpmconjs  31710  cyc3conja  31711  mbfmco  32531  eulerpartlemmf  32642  cvmliftmolem1  33542  cvmlift2lem9a  33564  cvmlift2lem9  33572  mclsppslem  33844  ftc1anclem3  35965  trlcocnv  38996  tendoicl  39072  cdlemk45  39223  rimco  40510  cononrel1  41531  cononrel2  41532  cnvtrcl0  41563  cnvtrrel  41607  relexpaddss  41655  frege131d  41701  brco2f1o  41971  brco3f1o  41972  clsneicnv  42044  neicvgnvo  42054  smfco  44685