Theorem f1ococnv1 6852

Description: The composition of a one-to-one onto function's converse and itself equals the identity relation restricted to the function's domain. (Contributed by NM, 13-Dec-2003.)

Assertion

Ref	Expression
f1ococnv1	⊢ (𝐹:𝐴–1-1-onto→𝐵 → (◡𝐹 ∘ 𝐹) = ( I ↾ 𝐴))

Proof of Theorem f1ococnv1

Step	Hyp	Ref	Expression
1		f1orel 6825	. . . 4 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → Rel 𝐹)
2		dfrel2 6189	. . . 4 ⊢ (Rel 𝐹 ↔ ◡◡𝐹 = 𝐹)
3	1, 2	sylib 221	. . 3 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → ◡◡𝐹 = 𝐹)
4	3	coeq2d 5850	. 2 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (◡𝐹 ∘ ◡◡𝐹) = (◡𝐹 ∘ 𝐹))
5		f1ocnv 6835	. . 3 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → ◡𝐹:𝐵–1-1-onto→𝐴)
6		f1ococnv2 6850	. . 3 ⊢ (◡𝐹:𝐵–1-1-onto→𝐴 → (◡𝐹 ∘ ◡◡𝐹) = ( I ↾ 𝐴))
7	5, 6	syl 18	. 2 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (◡𝐹 ∘ ◡◡𝐹) = ( I ↾ 𝐴))
8	4, 7	eqtr3d 2800	1 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (◡𝐹 ∘ 𝐹) = ( I ↾ 𝐴))

Syntax hints:   → wi 4   = wceq 1570   I cid 5557  ^◡ccnv 5662   ↾ cres 5665   ∘ ccom 5667  Rel wrel 5668  –1-1-onto→wf1o 6537

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-ext 2735  ax-sep 5258  ax-pr 5406

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1810  df-sb 2097  df-clab 2742  df-cleq 2755  df-clel 2838  df-ral 3080  df-rex 3090  df-rab 3417  df-v 3457  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4288  df-if 4489  df-sn 4591  df-pr 4593  df-op 4597  df-br 5111  df-opab 5175  df-id 5558  df-xp 5669  df-rel 5670  df-cnv 5671  df-co 5672  df-dm 5673  df-rn 5674  df-res 5675  df-fun 6540  df-fn 6541  df-f 6542  df-f1 6543  df-fo 6544  df-f1o 6545

This theorem is referenced by:  f1cocnv1  6853  f1ocnvfv1  7276  fcof1oinvd  7293  mapen  9130  mapfien  9369  hashfacen  14493  setcinv  18148  catcisolem  18168  symggrp  19471  f1omvdco2  19519  rngcinv  20723  ringcinv  20757  pf1mpf  22493  ufldom  24100  motgrp  28793  fmptco1f1o  32959  fcobij  33046  cocnvf1o  33055  symgfcoeu  33383  pmtrcnel2  33391  cycpmconjslem1  33455  cycpmconjslem2  33456  reprpmtf1o  34994  subfacp1lem5  35657  ltrncoidN  40883  trlcoabs2N  41477  trlcoat  41478  trlcone  41483  cdlemg47  41491  tgrpgrplem  41504  tendoipl  41552  cdlemi2  41574  cdlemk2  41587  cdlemk4  41589  cdlemk8  41593  tendocnv  41776  dvhgrp  41862  cdlemn8  41959  dihopelvalcpre  42003  aks6d1c6lem5  42925  dssmap2d  44731  rngcinvALTV  49024  ringcinvALTV  49058