Theorem funcsect 17779

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 2731	. . . . . . 7 ⊢ (Hom ‘𝐷) = (Hom ‘𝐷)
4		eqid 2731	. . . . . . 7 ⊢ (comp‘𝐷) = (comp‘𝐷)
5		eqid 2731	. . . . . . 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 5090	. . . . . . . . . 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 17770	. . . . . . . . 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 17660	. . . . . 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 6826	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑋)‘(𝑁(⟨𝑋, 𝑌⟩(comp‘𝐷)𝑋)𝑀)) = ((𝑋𝐺𝑋)‘((Id‘𝐷)‘𝑋)))
19		eqid 2731	. . . 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 17778	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑋)‘(𝑁(⟨𝑋, 𝑌⟩(comp‘𝐷)𝑋)𝑀)) = (((𝑌𝐺𝑋)‘𝑁)(⟨(𝐹‘𝑋), (𝐹‘𝑌)⟩(comp‘𝐸)(𝐹‘𝑋))((𝑋𝐺𝑌)‘𝑀)))
23		eqid 2731	. . . 4 ⊢ (Id‘𝐸) = (Id‘𝐸)
24	2, 5, 23, 7, 13	funcid 17777	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑋)‘((Id‘𝐷)‘𝑋)) = ((Id‘𝐸)‘(𝐹‘𝑋)))
25	18, 22, 24	3eqtr3d 2774	. 2 ⊢ (𝜑 → (((𝑌𝐺𝑋)‘𝑁)(⟨(𝐹‘𝑋), (𝐹‘𝑌)⟩(comp‘𝐸)(𝐹‘𝑋))((𝑋𝐺𝑌)‘𝑀)) = ((Id‘𝐸)‘(𝐹‘𝑋)))
26		eqid 2731	. . 3 ⊢ (Base‘𝐸) = (Base‘𝐸)
27		eqid 2731	. . 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 17773	. . . 4 ⊢ (𝜑 → 𝐹:𝐵⟶(Base‘𝐸))
31	30, 13	ffvelcdmd 7018	. . 3 ⊢ (𝜑 → (𝐹‘𝑋) ∈ (Base‘𝐸))
32	30, 14	ffvelcdmd 7018	. . 3 ⊢ (𝜑 → (𝐹‘𝑌) ∈ (Base‘𝐸))
33	2, 3, 27, 7, 13, 14	funcf2 17775	. . . 4 ⊢ (𝜑 → (𝑋𝐺𝑌):(𝑋(Hom ‘𝐷)𝑌)⟶((𝐹‘𝑋)(Hom ‘𝐸)(𝐹‘𝑌)))
34	33, 20	ffvelcdmd 7018	. . 3 ⊢ (𝜑 → ((𝑋𝐺𝑌)‘𝑀) ∈ ((𝐹‘𝑋)(Hom ‘𝐸)(𝐹‘𝑌)))
35	2, 3, 27, 7, 14, 13	funcf2 17775	. . . 4 ⊢ (𝜑 → (𝑌𝐺𝑋):(𝑌(Hom ‘𝐷)𝑋)⟶((𝐹‘𝑌)(Hom ‘𝐸)(𝐹‘𝑋)))
36	35, 21	ffvelcdmd 7018	. . 3 ⊢ (𝜑 → ((𝑌𝐺𝑋)‘𝑁) ∈ ((𝐹‘𝑌)(Hom ‘𝐸)(𝐹‘𝑋)))
37	26, 27, 19, 23, 28, 29, 31, 32, 34, 36	issect2 17661	. 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 1541   ∈ wcel 2111  ⟨cop 4579   class class class wbr 5089  ‘cfv 6481  (class class class)co 7346  Basecbs 17120  Hom chom 17172  compcco 17173  Catccat 17570  Idccid 17571  Sectcsect 17651   Func cfunc 17761

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2113  ax-9 2121  ax-10 2144  ax-11 2160  ax-12 2180  ax-ext 2703  ax-rep 5215  ax-sep 5232  ax-nul 5242  ax-pow 5301  ax-pr 5368  ax-un 7668

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-nf 1785  df-sb 2068  df-mo 2535  df-eu 2564  df-clab 2710  df-cleq 2723  df-clel 2806  df-nfc 2881  df-ne 2929  df-ral 3048  df-rex 3057  df-reu 3347  df-rab 3396  df-v 3438  df-sbc 3737  df-csb 3846  df-dif 3900  df-un 3902  df-in 3904  df-ss 3914  df-nul 4281  df-if 4473  df-pw 4549  df-sn 4574  df-pr 4576  df-op 4580  df-uni 4857  df-iun 4941  df-br 5090  df-opab 5152  df-mpt 5171  df-id 5509  df-xp 5620  df-rel 5621  df-cnv 5622  df-co 5623  df-dm 5624  df-rn 5625  df-res 5626  df-ima 5627  df-iota 6437  df-fun 6483  df-fn 6484  df-f 6485  df-f1 6486  df-fo 6487  df-f1o 6488  df-fv 6489  df-ov 7349  df-oprab 7350  df-mpo 7351  df-1st 7921  df-2nd 7922  df-map 8752  df-ixp 8822  df-sect 17654  df-func 17765

This theorem is referenced by:  funcinv  17780