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Theorem cofurid 16772
 Description: The identity functor is a right identity for composition. (Contributed by Mario Carneiro, 3-Jan-2017.)
Hypotheses
Ref Expression
cofulid.g (𝜑𝐹 ∈ (𝐶 Func 𝐷))
cofurid.1 𝐼 = (idfunc𝐶)
Assertion
Ref Expression
cofurid (𝜑 → (𝐹func 𝐼) = 𝐹)

Proof of Theorem cofurid
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 cofurid.1 . . . . . 6 𝐼 = (idfunc𝐶)
2 eqid 2760 . . . . . 6 (Base‘𝐶) = (Base‘𝐶)
3 cofulid.g . . . . . . . 8 (𝜑𝐹 ∈ (𝐶 Func 𝐷))
4 funcrcl 16744 . . . . . . . 8 (𝐹 ∈ (𝐶 Func 𝐷) → (𝐶 ∈ Cat ∧ 𝐷 ∈ Cat))
53, 4syl 17 . . . . . . 7 (𝜑 → (𝐶 ∈ Cat ∧ 𝐷 ∈ Cat))
65simpld 477 . . . . . 6 (𝜑𝐶 ∈ Cat)
71, 2, 6idfu1st 16760 . . . . 5 (𝜑 → (1st𝐼) = ( I ↾ (Base‘𝐶)))
87coeq2d 5440 . . . 4 (𝜑 → ((1st𝐹) ∘ (1st𝐼)) = ((1st𝐹) ∘ ( I ↾ (Base‘𝐶))))
9 eqid 2760 . . . . . 6 (Base‘𝐷) = (Base‘𝐷)
10 relfunc 16743 . . . . . . 7 Rel (𝐶 Func 𝐷)
11 1st2ndbr 7385 . . . . . . 7 ((Rel (𝐶 Func 𝐷) ∧ 𝐹 ∈ (𝐶 Func 𝐷)) → (1st𝐹)(𝐶 Func 𝐷)(2nd𝐹))
1210, 3, 11sylancr 698 . . . . . 6 (𝜑 → (1st𝐹)(𝐶 Func 𝐷)(2nd𝐹))
132, 9, 12funcf1 16747 . . . . 5 (𝜑 → (1st𝐹):(Base‘𝐶)⟶(Base‘𝐷))
14 fcoi1 6239 . . . . 5 ((1st𝐹):(Base‘𝐶)⟶(Base‘𝐷) → ((1st𝐹) ∘ ( I ↾ (Base‘𝐶))) = (1st𝐹))
1513, 14syl 17 . . . 4 (𝜑 → ((1st𝐹) ∘ ( I ↾ (Base‘𝐶))) = (1st𝐹))
168, 15eqtrd 2794 . . 3 (𝜑 → ((1st𝐹) ∘ (1st𝐼)) = (1st𝐹))
1773ad2ant1 1128 . . . . . . . . . 10 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → (1st𝐼) = ( I ↾ (Base‘𝐶)))
1817fveq1d 6355 . . . . . . . . 9 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → ((1st𝐼)‘𝑥) = (( I ↾ (Base‘𝐶))‘𝑥))
19 fvresi 6604 . . . . . . . . . 10 (𝑥 ∈ (Base‘𝐶) → (( I ↾ (Base‘𝐶))‘𝑥) = 𝑥)
20193ad2ant2 1129 . . . . . . . . 9 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → (( I ↾ (Base‘𝐶))‘𝑥) = 𝑥)
2118, 20eqtrd 2794 . . . . . . . 8 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → ((1st𝐼)‘𝑥) = 𝑥)
2217fveq1d 6355 . . . . . . . . 9 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → ((1st𝐼)‘𝑦) = (( I ↾ (Base‘𝐶))‘𝑦))
23 fvresi 6604 . . . . . . . . . 10 (𝑦 ∈ (Base‘𝐶) → (( I ↾ (Base‘𝐶))‘𝑦) = 𝑦)
24233ad2ant3 1130 . . . . . . . . 9 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → (( I ↾ (Base‘𝐶))‘𝑦) = 𝑦)
2522, 24eqtrd 2794 . . . . . . . 8 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → ((1st𝐼)‘𝑦) = 𝑦)
2621, 25oveq12d 6832 . . . . . . 7 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → (((1st𝐼)‘𝑥)(2nd𝐹)((1st𝐼)‘𝑦)) = (𝑥(2nd𝐹)𝑦))
2763ad2ant1 1128 . . . . . . . 8 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → 𝐶 ∈ Cat)
28 eqid 2760 . . . . . . . 8 (Hom ‘𝐶) = (Hom ‘𝐶)
29 simp2 1132 . . . . . . . 8 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → 𝑥 ∈ (Base‘𝐶))
30 simp3 1133 . . . . . . . 8 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → 𝑦 ∈ (Base‘𝐶))
311, 2, 27, 28, 29, 30idfu2nd 16758 . . . . . . 7 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → (𝑥(2nd𝐼)𝑦) = ( I ↾ (𝑥(Hom ‘𝐶)𝑦)))
3226, 31coeq12d 5442 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → ((((1st𝐼)‘𝑥)(2nd𝐹)((1st𝐼)‘𝑦)) ∘ (𝑥(2nd𝐼)𝑦)) = ((𝑥(2nd𝐹)𝑦) ∘ ( I ↾ (𝑥(Hom ‘𝐶)𝑦))))
33 eqid 2760 . . . . . . . 8 (Hom ‘𝐷) = (Hom ‘𝐷)
34123ad2ant1 1128 . . . . . . . 8 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → (1st𝐹)(𝐶 Func 𝐷)(2nd𝐹))
352, 28, 33, 34, 29, 30funcf2 16749 . . . . . . 7 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → (𝑥(2nd𝐹)𝑦):(𝑥(Hom ‘𝐶)𝑦)⟶(((1st𝐹)‘𝑥)(Hom ‘𝐷)((1st𝐹)‘𝑦)))
36 fcoi1 6239 . . . . . . 7 ((𝑥(2nd𝐹)𝑦):(𝑥(Hom ‘𝐶)𝑦)⟶(((1st𝐹)‘𝑥)(Hom ‘𝐷)((1st𝐹)‘𝑦)) → ((𝑥(2nd𝐹)𝑦) ∘ ( I ↾ (𝑥(Hom ‘𝐶)𝑦))) = (𝑥(2nd𝐹)𝑦))
3735, 36syl 17 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → ((𝑥(2nd𝐹)𝑦) ∘ ( I ↾ (𝑥(Hom ‘𝐶)𝑦))) = (𝑥(2nd𝐹)𝑦))
3832, 37eqtrd 2794 . . . . 5 ((𝜑𝑥 ∈ (Base‘𝐶) ∧ 𝑦 ∈ (Base‘𝐶)) → ((((1st𝐼)‘𝑥)(2nd𝐹)((1st𝐼)‘𝑦)) ∘ (𝑥(2nd𝐼)𝑦)) = (𝑥(2nd𝐹)𝑦))
3938mpt2eq3dva 6885 . . . 4 (𝜑 → (𝑥 ∈ (Base‘𝐶), 𝑦 ∈ (Base‘𝐶) ↦ ((((1st𝐼)‘𝑥)(2nd𝐹)((1st𝐼)‘𝑦)) ∘ (𝑥(2nd𝐼)𝑦))) = (𝑥 ∈ (Base‘𝐶), 𝑦 ∈ (Base‘𝐶) ↦ (𝑥(2nd𝐹)𝑦)))
402, 12funcfn2 16750 . . . . 5 (𝜑 → (2nd𝐹) Fn ((Base‘𝐶) × (Base‘𝐶)))
41 fnov 6934 . . . . 5 ((2nd𝐹) Fn ((Base‘𝐶) × (Base‘𝐶)) ↔ (2nd𝐹) = (𝑥 ∈ (Base‘𝐶), 𝑦 ∈ (Base‘𝐶) ↦ (𝑥(2nd𝐹)𝑦)))
4240, 41sylib 208 . . . 4 (𝜑 → (2nd𝐹) = (𝑥 ∈ (Base‘𝐶), 𝑦 ∈ (Base‘𝐶) ↦ (𝑥(2nd𝐹)𝑦)))
4339, 42eqtr4d 2797 . . 3 (𝜑 → (𝑥 ∈ (Base‘𝐶), 𝑦 ∈ (Base‘𝐶) ↦ ((((1st𝐼)‘𝑥)(2nd𝐹)((1st𝐼)‘𝑦)) ∘ (𝑥(2nd𝐼)𝑦))) = (2nd𝐹))
4416, 43opeq12d 4561 . 2 (𝜑 → ⟨((1st𝐹) ∘ (1st𝐼)), (𝑥 ∈ (Base‘𝐶), 𝑦 ∈ (Base‘𝐶) ↦ ((((1st𝐼)‘𝑥)(2nd𝐹)((1st𝐼)‘𝑦)) ∘ (𝑥(2nd𝐼)𝑦)))⟩ = ⟨(1st𝐹), (2nd𝐹)⟩)
451idfucl 16762 . . . 4 (𝐶 ∈ Cat → 𝐼 ∈ (𝐶 Func 𝐶))
466, 45syl 17 . . 3 (𝜑𝐼 ∈ (𝐶 Func 𝐶))
472, 46, 3cofuval 16763 . 2 (𝜑 → (𝐹func 𝐼) = ⟨((1st𝐹) ∘ (1st𝐼)), (𝑥 ∈ (Base‘𝐶), 𝑦 ∈ (Base‘𝐶) ↦ ((((1st𝐼)‘𝑥)(2nd𝐹)((1st𝐼)‘𝑦)) ∘ (𝑥(2nd𝐼)𝑦)))⟩)
48 1st2nd 7382 . . 3 ((Rel (𝐶 Func 𝐷) ∧ 𝐹 ∈ (𝐶 Func 𝐷)) → 𝐹 = ⟨(1st𝐹), (2nd𝐹)⟩)
4910, 3, 48sylancr 698 . 2 (𝜑𝐹 = ⟨(1st𝐹), (2nd𝐹)⟩)
5044, 47, 493eqtr4d 2804 1 (𝜑 → (𝐹func 𝐼) = 𝐹)
 Colors of variables: wff setvar class Syntax hints:   → wi 4   ∧ wa 383   ∧ w3a 1072   = wceq 1632   ∈ wcel 2139  ⟨cop 4327   class class class wbr 4804   I cid 5173   × cxp 5264   ↾ cres 5268   ∘ ccom 5270  Rel wrel 5271   Fn wfn 6044  ⟶wf 6045  ‘cfv 6049  (class class class)co 6814   ↦ cmpt2 6816  1st c1st 7332  2nd c2nd 7333  Basecbs 16079  Hom chom 16174  Catccat 16546   Func cfunc 16735  idfunccidfu 16736   ∘func ccofu 16737 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1871  ax-4 1886  ax-5 1988  ax-6 2054  ax-7 2090  ax-8 2141  ax-9 2148  ax-10 2168  ax-11 2183  ax-12 2196  ax-13 2391  ax-ext 2740  ax-rep 4923  ax-sep 4933  ax-nul 4941  ax-pow 4992  ax-pr 5055  ax-un 7115 This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3an 1074  df-tru 1635  df-ex 1854  df-nf 1859  df-sb 2047  df-eu 2611  df-mo 2612  df-clab 2747  df-cleq 2753  df-clel 2756  df-nfc 2891  df-ne 2933  df-ral 3055  df-rex 3056  df-reu 3057  df-rmo 3058  df-rab 3059  df-v 3342  df-sbc 3577  df-csb 3675  df-dif 3718  df-un 3720  df-in 3722  df-ss 3729  df-nul 4059  df-if 4231  df-pw 4304  df-sn 4322  df-pr 4324  df-op 4328  df-uni 4589  df-iun 4674  df-br 4805  df-opab 4865  df-mpt 4882  df-id 5174  df-xp 5272  df-rel 5273  df-cnv 5274  df-co 5275  df-dm 5276  df-rn 5277  df-res 5278  df-ima 5279  df-iota 6012  df-fun 6051  df-fn 6052  df-f 6053  df-f1 6054  df-fo 6055  df-f1o 6056  df-fv 6057  df-riota 6775  df-ov 6817  df-oprab 6818  df-mpt2 6819  df-1st 7334  df-2nd 7335  df-map 8027  df-ixp 8077  df-cat 16550  df-cid 16551  df-func 16739  df-idfu 16740  df-cofu 16741 This theorem is referenced by:  catccatid  16973
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