Theorem f1ococnv1 6811

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 6785	. . . 4 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → Rel 𝐹)
2		dfrel2 6155	. . . 4 ⊢ (Rel 𝐹 ↔ ◡◡𝐹 = 𝐹)
3	1, 2	sylib 218	. . 3 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → ◡◡𝐹 = 𝐹)
4	3	coeq2d 5819	. 2 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (◡𝐹 ∘ ◡◡𝐹) = (◡𝐹 ∘ 𝐹))
5		f1ocnv 6794	. . 3 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → ◡𝐹:𝐵–1-1-onto→𝐴)
6		f1ococnv2 6809	. . 3 ⊢ (◡𝐹:𝐵–1-1-onto→𝐴 → (◡𝐹 ∘ ◡◡𝐹) = ( I ↾ 𝐴))
7	5, 6	syl 17	. 2 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (◡𝐹 ∘ ◡◡𝐹) = ( I ↾ 𝐴))
8	4, 7	eqtr3d 2774	1 ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (◡𝐹 ∘ 𝐹) = ( I ↾ 𝐴))

Syntax hints:   → wi 4   = wceq 1542   I cid 5526  ^◡ccnv 5631   ↾ cres 5634   ∘ ccom 5636  Rel wrel 5637  –1-1-onto→wf1o 6499

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 5243  ax-pr 5379

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-ral 3053  df-rex 3063  df-rab 3402  df-v 3444  df-dif 3906  df-un 3908  df-in 3910  df-ss 3920  df-nul 4288  df-if 4482  df-sn 4583  df-pr 4585  df-op 4589  df-br 5101  df-opab 5163  df-id 5527  df-xp 5638  df-rel 5639  df-cnv 5640  df-co 5641  df-dm 5642  df-rn 5643  df-res 5644  df-fun 6502  df-fn 6503  df-f 6504  df-f1 6505  df-fo 6506  df-f1o 6507

This theorem is referenced by:  f1cocnv1  6812  f1ocnvfv1  7232  fcof1oinvd  7249  mapen  9081  mapfien  9323  hashfacen  14389  setcinv  18026  catcisolem  18046  symggrp  19341  f1omvdco2  19389  rngcinv  20582  ringcinv  20616  pf1mpf  22308  ufldom  23918  motgrp  28627  fmptco1f1o  32722  fcobij  32809  cocnvf1o  32818  symgfcoeu  33175  pmtrcnel2  33183  cycpmconjslem1  33247  cycpmconjslem2  33248  reprpmtf1o  34803  subfacp1lem5  35397  ltrncoidN  40501  trlcoabs2N  41095  trlcoat  41096  trlcone  41101  cdlemg47  41109  tgrpgrplem  41122  tendoipl  41170  cdlemi2  41192  cdlemk2  41205  cdlemk4  41207  cdlemk8  41211  tendocnv  41394  dvhgrp  41480  cdlemn8  41577  dihopelvalcpre  41621  aks6d1c6lem5  42544  dssmap2d  44375  rngcinvALTV  48633  ringcinvALTV  48667