Theorem fundcmpsurinj 48764

Description: Every function 𝐹:𝐴⟶𝐵 can be decomposed into a surjective and an injective function. (Contributed by AV, 13-Mar-2024.)

Assertion

Ref	Expression
fundcmpsurinj	⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ 𝑉) → ∃𝑔∃ℎ∃𝑝(𝑔:𝐴⟶onto𝑝 ∧ ℎ:𝑝⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)))

Distinct variable groups:   𝐴,𝑔,ℎ,𝑝   𝐵,𝑔,ℎ,𝑝   𝑔,𝐹,ℎ,𝑝   𝑔,𝑉

Allowed substitution hints:   𝑉(ℎ, 𝑝)

Proof of Theorem fundcmpsurinj

Dummy variables 𝑥 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		abrexexg 8007	. . . 4 ⊢ (𝐴 ∈ 𝑉 → {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} ∈ V)
2	1	adantl 487	. . 3 ⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ 𝑉) → {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} ∈ V)
3		fveq2 6916	. . . . . . . . 9 ⊢ (𝑥 = 𝑦 → (𝐹‘𝑥) = (𝐹‘𝑦))
4	3	sneqd 4596	. . . . . . . 8 ⊢ (𝑥 = 𝑦 → {(𝐹‘𝑥)} = {(𝐹‘𝑦)})
5	4	imaeq2d 6070	. . . . . . 7 ⊢ (𝑥 = 𝑦 → (◡𝐹 “ {(𝐹‘𝑥)}) = (◡𝐹 “ {(𝐹‘𝑦)}))
6	5	eqeq2d 2774	. . . . . 6 ⊢ (𝑥 = 𝑦 → (𝑧 = (◡𝐹 “ {(𝐹‘𝑥)}) ↔ 𝑧 = (◡𝐹 “ {(𝐹‘𝑦)})))
7	6	cbvrexvw 3245	. . . . 5 ⊢ (∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)}) ↔ ∃𝑦 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑦)}))
8	7	abbii 2830	. . . 4 ⊢ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} = {𝑧 ∣ ∃𝑦 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑦)})}
9	8	fundcmpsurinjpreimafv 48763	. . 3 ⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ 𝑉) → ∃𝑔∃ℎ(𝑔:𝐴⟶onto{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} ∧ ℎ:{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})}⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)))
10		foeq3 6824	. . . . 5 ⊢ (𝑝 = {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} → (𝑔:𝐴⟶onto𝑝 ↔ 𝑔:𝐴⟶onto{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})}))
11		f1eq2 6804	. . . . 5 ⊢ (𝑝 = {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} → (ℎ:𝑝⟶1-1𝐵 ↔ ℎ:{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})}⟶1-1𝐵))
12	10, 11	3anbi12d 1466	. . . 4 ⊢ (𝑝 = {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} → ((𝑔:𝐴⟶onto𝑝 ∧ ℎ:𝑝⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)) ↔ (𝑔:𝐴⟶onto{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} ∧ ℎ:{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})}⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔))))
13	12	2exbidv 1959	. . 3 ⊢ (𝑝 = {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} → (∃𝑔∃ℎ(𝑔:𝐴⟶onto𝑝 ∧ ℎ:𝑝⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)) ↔ ∃𝑔∃ℎ(𝑔:𝐴⟶onto{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})} ∧ ℎ:{𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = (◡𝐹 “ {(𝐹‘𝑥)})}⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔))))
14	2, 9, 13	spcedv 3556	. 2 ⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ 𝑉) → ∃𝑝∃𝑔∃ℎ(𝑔:𝐴⟶onto𝑝 ∧ ℎ:𝑝⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)))
15		exrot3 2205	. 2 ⊢ (∃𝑝∃𝑔∃ℎ(𝑔:𝐴⟶onto𝑝 ∧ ℎ:𝑝⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)) ↔ ∃𝑔∃ℎ∃𝑝(𝑔:𝐴⟶onto𝑝 ∧ ℎ:𝑝⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)))
16	14, 15	sylib 221	1 ⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ 𝑉) → ∃𝑔∃ℎ∃𝑝(𝑔:𝐴⟶onto𝑝 ∧ ℎ:𝑝⟶1-1𝐵 ∧ 𝐹 = (ℎ ∘ 𝑔)))

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   ∧ w3a 1103   = wceq 1570  ∃wex 1812   ∈ wcel 2147  {cab 2741  ∃wrex 3090  Vcvv 3454  {csn 4588  ^◡ccnv 5657   “ cima 5661   ∘ ccom 5662  ⟶wf 6562  ⟶1-1wf1 6563  ⟶ontowfo 6564  ‘cfv 6566

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-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735  ax-rep 5238  ax-sep 5255  ax-nul 5266  ax-pow 5334  ax-pr 5398  ax-un 7783

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-nf 1817  df-sb 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ne 2960  df-nel 3066  df-ral 3081  df-rex 3091  df-reu 3370  df-rab 3417  df-v 3456  df-sbc 3743  df-csb 3852  df-ss 3901  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-pw 4562  df-sn 4589  df-pr 4591  df-op 4841  df-uni 4873  df-iun 4958  df-br 5109  df-opab 5174  df-mpt 5193  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-ima 5671  df-iota 6520  df-fun 6568  df-fn 6569  df-f 6570  df-f1 6571  df-fo 6572  df-f1o 6573  df-fv 6574

This theorem is used by: (None)