Theorem funcsect 17888

Description: The image of a section under a functor is a section. (Contributed by Mario Carneiro, 2-Jan-2017.)

Hypotheses

Ref	Expression
funcsect.b	⊢ 𝐵 = (Base‘𝐷)
funcsect.s	⊢ 𝑆 = (Sect‘𝐷)
funcsect.t	⊢ 𝑇 = (Sect‘𝐸)
funcsect.f	⊢ (𝜑 → 𝐹(𝐷 Func 𝐸)𝐺)
funcsect.x	⊢ (𝜑 → 𝑋 ∈ 𝐵)
funcsect.y	⊢ (𝜑 → 𝑌 ∈ 𝐵)
funcsect.m	⊢ (𝜑 → 𝑀(𝑋𝑆𝑌)𝑁)

Assertion

Ref	Expression
funcsect	⊢ (𝜑 → ((𝑋𝐺𝑌)‘𝑀)((𝐹‘𝑋)𝑇(𝐹‘𝑌))((𝑌𝐺𝑋)‘𝑁))

Proof of Theorem funcsect

Step	Hyp	Ref	Expression
1		funcsect.m	. . . . . 6 ⊢ (𝜑 → 𝑀(𝑋𝑆𝑌)𝑁)
2		funcsect.b	. . . . . . 7 ⊢ 𝐵 = (Base‘𝐷)
3		eqid 2734	. . . . . . 7 ⊢ (Hom ‘𝐷) = (Hom ‘𝐷)
4		eqid 2734	. . . . . . 7 ⊢ (comp‘𝐷) = (comp‘𝐷)
5		eqid 2734	. . . . . . 7 ⊢ (Id‘𝐷) = (Id‘𝐷)
6		funcsect.s	. . . . . . 7 ⊢ 𝑆 = (Sect‘𝐷)
7		funcsect.f	. . . . . . . . . 10 ⊢ (𝜑 → 𝐹(𝐷 Func 𝐸)𝐺)
8		df-br 5124	. . . . . . . . . 10 ⊢ (𝐹(𝐷 Func 𝐸)𝐺 ↔ ⟨𝐹, 𝐺⟩ ∈ (𝐷 Func 𝐸))
9	7, 8	sylib 218	. . . . . . . . 9 ⊢ (𝜑 → ⟨𝐹, 𝐺⟩ ∈ (𝐷 Func 𝐸))
10		funcrcl 17879	. . . . . . . . 9 ⊢ (⟨𝐹, 𝐺⟩ ∈ (𝐷 Func 𝐸) → (𝐷 ∈ Cat ∧ 𝐸 ∈ Cat))
11	9, 10	syl 17	. . . . . . . 8 ⊢ (𝜑 → (𝐷 ∈ Cat ∧ 𝐸 ∈ Cat))
12	11	simpld 494	. . . . . . 7 ⊢ (𝜑 → 𝐷 ∈ Cat)
13		funcsect.x	. . . . . . 7 ⊢ (𝜑 → 𝑋 ∈ 𝐵)
14		funcsect.y	. . . . . . 7 ⊢ (𝜑 → 𝑌 ∈ 𝐵)
15	2, 3, 4, 5, 6, 12, 13, 14	issect 17768	. . . . . 6 ⊢ (𝜑 → (𝑀(𝑋𝑆𝑌)𝑁 ↔ (𝑀 ∈ (𝑋(Hom ‘𝐷)𝑌) ∧ 𝑁 ∈ (𝑌(Hom ‘𝐷)𝑋) ∧ (𝑁(⟨𝑋, 𝑌⟩(comp‘𝐷)𝑋)𝑀) = ((Id‘𝐷)‘𝑋))))
16	1, 15	mpbid 232	. . . . 5 ⊢ (𝜑 → (𝑀 ∈ (𝑋(Hom ‘𝐷)𝑌) ∧ 𝑁 ∈ (𝑌(Hom ‘𝐷)𝑋) ∧ (𝑁(⟨𝑋, 𝑌⟩(comp‘𝐷)𝑋)𝑀) = ((Id‘𝐷)‘𝑋)))
17	16	simp3d 1144	. . . 4 ⊢ (𝜑 → (𝑁(⟨𝑋, 𝑌⟩(comp‘𝐷)𝑋)𝑀) = ((Id‘𝐷)‘𝑋))
18	17	fveq2d 6890	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑋)‘(𝑁(⟨𝑋, 𝑌⟩(comp‘𝐷)𝑋)𝑀)) = ((𝑋𝐺𝑋)‘((Id‘𝐷)‘𝑋)))
19		eqid 2734	. . . 4 ⊢ (comp‘𝐸) = (comp‘𝐸)
20	16	simp1d 1142	. . . 4 ⊢ (𝜑 → 𝑀 ∈ (𝑋(Hom ‘𝐷)𝑌))
21	16	simp2d 1143	. . . 4 ⊢ (𝜑 → 𝑁 ∈ (𝑌(Hom ‘𝐷)𝑋))
22	2, 3, 4, 19, 7, 13, 14, 13, 20, 21	funcco 17887	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑋)‘(𝑁(⟨𝑋, 𝑌⟩(comp‘𝐷)𝑋)𝑀)) = (((𝑌𝐺𝑋)‘𝑁)(⟨(𝐹‘𝑋), (𝐹‘𝑌)⟩(comp‘𝐸)(𝐹‘𝑋))((𝑋𝐺𝑌)‘𝑀)))
23		eqid 2734	. . . 4 ⊢ (Id‘𝐸) = (Id‘𝐸)
24	2, 5, 23, 7, 13	funcid 17886	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑋)‘((Id‘𝐷)‘𝑋)) = ((Id‘𝐸)‘(𝐹‘𝑋)))
25	18, 22, 24	3eqtr3d 2777	. 2 ⊢ (𝜑 → (((𝑌𝐺𝑋)‘𝑁)(⟨(𝐹‘𝑋), (𝐹‘𝑌)⟩(comp‘𝐸)(𝐹‘𝑋))((𝑋𝐺𝑌)‘𝑀)) = ((Id‘𝐸)‘(𝐹‘𝑋)))
26		eqid 2734	. . 3 ⊢ (Base‘𝐸) = (Base‘𝐸)
27		eqid 2734	. . 3 ⊢ (Hom ‘𝐸) = (Hom ‘𝐸)
28		funcsect.t	. . 3 ⊢ 𝑇 = (Sect‘𝐸)
29	11	simprd 495	. . 3 ⊢ (𝜑 → 𝐸 ∈ Cat)
30	2, 26, 7	funcf1 17882	. . . 4 ⊢ (𝜑 → 𝐹:𝐵⟶(Base‘𝐸))
31	30, 13	ffvelcdmd 7085	. . 3 ⊢ (𝜑 → (𝐹‘𝑋) ∈ (Base‘𝐸))
32	30, 14	ffvelcdmd 7085	. . 3 ⊢ (𝜑 → (𝐹‘𝑌) ∈ (Base‘𝐸))
33	2, 3, 27, 7, 13, 14	funcf2 17884	. . . 4 ⊢ (𝜑 → (𝑋𝐺𝑌):(𝑋(Hom ‘𝐷)𝑌)⟶((𝐹‘𝑋)(Hom ‘𝐸)(𝐹‘𝑌)))
34	33, 20	ffvelcdmd 7085	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑌)‘𝑀) ∈ ((𝐹‘𝑋)(Hom ‘𝐸)(𝐹‘𝑌)))
35	2, 3, 27, 7, 14, 13	funcf2 17884	. . . 4 ⊢ (𝜑 → (𝑌𝐺𝑋):(𝑌(Hom ‘𝐷)𝑋)⟶((𝐹‘𝑌)(Hom ‘𝐸)(𝐹‘𝑋)))
36	35, 21	ffvelcdmd 7085	. . 3 ⊢ (𝜑 → ((𝑌𝐺𝑋)‘𝑁) ∈ ((𝐹‘𝑌)(Hom ‘𝐸)(𝐹‘𝑋)))
37	26, 27, 19, 23, 28, 29, 31, 32, 34, 36	issect2 17769	. 2 ⊢ (𝜑 → (((𝑋𝐺𝑌)‘𝑀)((𝐹‘𝑋)𝑇(𝐹‘𝑌))((𝑌𝐺𝑋)‘𝑁) ↔ (((𝑌𝐺𝑋)‘𝑁)(⟨(𝐹‘𝑋), (𝐹‘𝑌)⟩(comp‘𝐸)(𝐹‘𝑋))((𝑋𝐺𝑌)‘𝑀)) = ((Id‘𝐸)‘(𝐹‘𝑋))))
38	25, 37	mpbird 257	1 ⊢ (𝜑 → ((𝑋𝐺𝑌)‘𝑀)((𝐹‘𝑋)𝑇(𝐹‘𝑌))((𝑌𝐺𝑋)‘𝑁))

Syntax hints:   → wi 4   ∧ wa 395   ∧ w3a 1086   = wceq 1539   ∈ wcel 2107  ⟨cop 4612   class class class wbr 5123  ‘cfv 6541  (class class class)co 7413  Basecbs 17229  Hom chom 17284  compcco 17285  Catccat 17678  Idccid 17679  Sectcsect 17759   Func cfunc 17870

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1794  ax-4 1808  ax-5 1909  ax-6 1966  ax-7 2006  ax-8 2109  ax-9 2117  ax-10 2140  ax-11 2156  ax-12 2176  ax-ext 2706  ax-rep 5259  ax-sep 5276  ax-nul 5286  ax-pow 5345  ax-pr 5412  ax-un 7737

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1779  df-nf 1783  df-sb 2064  df-mo 2538  df-eu 2567  df-clab 2713  df-cleq 2726  df-clel 2808  df-nfc 2884  df-ne 2932  df-ral 3051  df-rex 3060  df-reu 3364  df-rab 3420  df-v 3465  df-sbc 3771  df-csb 3880  df-dif 3934  df-un 3936  df-in 3938  df-ss 3948  df-nul 4314  df-if 4506  df-pw 4582  df-sn 4607  df-pr 4609  df-op 4613  df-uni 4888  df-iun 4973  df-br 5124  df-opab 5186  df-mpt 5206  df-id 5558  df-xp 5671  df-rel 5672  df-cnv 5673  df-co 5674  df-dm 5675  df-rn 5676  df-res 5677  df-ima 5678  df-iota 6494  df-fun 6543  df-fn 6544  df-f 6545  df-f1 6546  df-fo 6547  df-f1o 6548  df-fv 6549  df-ov 7416  df-oprab 7417  df-mpo 7418  df-1st 7996  df-2nd 7997  df-map 8850  df-ixp 8920  df-sect 17762  df-func 17874

This theorem is referenced by:  funcinv  17889