Theorem fcoi1 6786

Description: Composition of a mapping and restricted identity. (Contributed by NM, 13-Dec-2003.) (Proof shortened by Andrew Salmon, 17-Sep-2011.)

Assertion

Ref	Expression
fcoi1	⊢ (𝐹:𝐴⟶𝐵 → (𝐹 ∘ ( I ↾ 𝐴)) = 𝐹)

Proof of Theorem fcoi1

Step	Hyp	Ref	Expression
1		ffn 6739	. 2 ⊢ (𝐹:𝐴⟶𝐵 → 𝐹 Fn 𝐴)
2		df-fn 6569	. . 3 ⊢ (𝐹 Fn 𝐴 ↔ (Fun 𝐹 ∧ dom 𝐹 = 𝐴))
3		eqimss 3971	. . . . 5 ⊢ (dom 𝐹 = 𝐴 → dom 𝐹 ⊆ 𝐴)
4		cnvi 5875	. . . . . . . . . 10 ⊢ ◡ I = I
5	4	reseq1i 5982	. . . . . . . . 9 ⊢ (◡ I ↾ 𝐴) = ( I ↾ 𝐴)
6	5	cnveqi 5864	. . . . . . . 8 ⊢ ◡(◡ I ↾ 𝐴) = ◡( I ↾ 𝐴)
7		cnvresid 6287	. . . . . . . 8 ⊢ ◡( I ↾ 𝐴) = ( I ↾ 𝐴)
8	6, 7	eqtr2i 2787	. . . . . . 7 ⊢ ( I ↾ 𝐴) = ◡(◡ I ↾ 𝐴)
9	8	coeq2i 5849	. . . . . 6 ⊢ (𝐹 ∘ ( I ↾ 𝐴)) = (𝐹 ∘ ◡(◡ I ↾ 𝐴))
10		cores2 6280	. . . . . 6 ⊢ (dom 𝐹 ⊆ 𝐴 → (𝐹 ∘ ◡(◡ I ↾ 𝐴)) = (𝐹 ∘ I ))
11	9, 10	eqtrid 2810	. . . . 5 ⊢ (dom 𝐹 ⊆ 𝐴 → (𝐹 ∘ ( I ↾ 𝐴)) = (𝐹 ∘ I ))
12	3, 11	syl 18	. . . 4 ⊢ (dom 𝐹 = 𝐴 → (𝐹 ∘ ( I ↾ 𝐴)) = (𝐹 ∘ I ))
13		funrel 6584	. . . . 5 ⊢ (Fun 𝐹 → Rel 𝐹)
14		coi1 6285	. . . . 5 ⊢ (Rel 𝐹 → (𝐹 ∘ I ) = 𝐹)
15	13, 14	syl 18	. . . 4 ⊢ (Fun 𝐹 → (𝐹 ∘ I ) = 𝐹)
16	12, 15	sylan9eqr 2820	. . 3 ⊢ ((Fun 𝐹 ∧ dom 𝐹 = 𝐴) → (𝐹 ∘ ( I ↾ 𝐴)) = 𝐹)
17	2, 16	sylbi 220	. 2 ⊢ (𝐹 Fn 𝐴 → (𝐹 ∘ ( I ↾ 𝐴)) = 𝐹)
18	1, 17	syl 18	1 ⊢ (𝐹:𝐴⟶𝐵 → (𝐹 ∘ ( I ↾ 𝐴)) = 𝐹)

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   = wceq 1570   ⊆ wss 3900   I cid 5552  ^◡ccnv 5657  dom cdm 5658   ↾ cres 5660   ∘ ccom 5662  Rel wrel 5663  Fun wfun 6560   Fn wfn 6561  ⟶wf 6562

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-ext 2735  ax-sep 5255  ax-pr 5398

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-sb 2102  df-clab 2742  df-cleq 2755  df-clel 2839  df-ral 3081  df-rex 3091  df-rab 3417  df-v 3456  df-ss 3901  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-sn 4589  df-pr 4591  df-op 4841  df-br 5109  df-opab 5174  df-id 5553  df-xp 5664  df-rel 5665  df-cnv 5666  df-co 5667  df-dm 5668  df-rn 5669  df-res 5670  df-fun 6568  df-fn 6569  df-f 6570

This theorem is used by:  fcof1oinvd  7332  mapen  9198  mapfien  9437  hashfacen  14640  cofurid  18116  setccatid  18309  estrccatid  18356  curf2ndf  18471  efmndid  19134  efmndmnd  19135  f1omvdco2  19713  psgnunilem1  19758  pf1mpf  22725  pf1ind  22728  wilthlem3  27454  hoico1  32415  fmptco1f1o  33325  fcobijfs  33409  cocnvf1o  33417  cycpmconjslem2  33815  cycpmconjs  33816  cyc3conja  33817  1arithidomlem2  34172  mplvrpmga  34288  mplvrpmrhm  34290  reprpmtf1o  35366  ltrncoidN  41451  trlcoabs2N  42045  trlcoat  42046  cdlemg47a  42057  cdlemg46  42058  trljco  42063  tendo1mulr  42094  tendo0co2  42111  cdlemi2  42142  cdlemk2  42155  cdlemk4  42157  cdlemk8  42161  cdlemk53  42280  cdlemk55a  42282  dvhopN  42439  dihopelvalcpre  42571  dihmeetlem1N  42613  dihglblem5apreN  42614  diophrw  44036  mendring  44451  rngccatidALTV  49642  ringccatidALTV  49676  fucoridid  50817