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Theorem fundcmpsurinjALT 44922
Description: Alternate proof of fundcmpsurinj 44919, based on fundcmpsurinjimaid 44921: Every function 𝐹:𝐴𝐵 can be decomposed into a surjective and an injective function. (Proof modification is discouraged.) (New usage is discouraged.) (Contributed by AV, 13-Mar-2024.)
Assertion
Ref Expression
fundcmpsurinjALT ((𝐹:𝐴𝐵𝐴𝑉) → ∃𝑔𝑝(𝑔:𝐴onto𝑝:𝑝1-1𝐵𝐹 = (𝑔)))
Distinct variable groups:   𝐴,𝑔,,𝑝   𝐵,𝑔,,𝑝   𝑔,𝐹,,𝑝
Allowed substitution hints:   𝑉(𝑔,,𝑝)

Proof of Theorem fundcmpsurinjALT
Dummy variable 𝑦 is distinct from all other variables.
StepHypRef Expression
1 mptexg 7129 . . . 4 (𝐴𝑉 → (𝑦𝐴 ↦ (𝐹𝑦)) ∈ V)
21adantl 483 . . 3 ((𝐹:𝐴𝐵𝐴𝑉) → (𝑦𝐴 ↦ (𝐹𝑦)) ∈ V)
3 ffun 6633 . . . . 5 (𝐹:𝐴𝐵 → Fun 𝐹)
4 funimaexg 6549 . . . . 5 ((Fun 𝐹𝐴𝑉) → (𝐹𝐴) ∈ V)
53, 4sylan 581 . . . 4 ((𝐹:𝐴𝐵𝐴𝑉) → (𝐹𝐴) ∈ V)
65resiexd 7124 . . 3 ((𝐹:𝐴𝐵𝐴𝑉) → ( I ↾ (𝐹𝐴)) ∈ V)
72, 6, 53jca 1128 . 2 ((𝐹:𝐴𝐵𝐴𝑉) → ((𝑦𝐴 ↦ (𝐹𝑦)) ∈ V ∧ ( I ↾ (𝐹𝐴)) ∈ V ∧ (𝐹𝐴) ∈ V))
8 eqid 2736 . . . 4 (𝐹𝐴) = (𝐹𝐴)
9 eqid 2736 . . . 4 (𝑦𝐴 ↦ (𝐹𝑦)) = (𝑦𝐴 ↦ (𝐹𝑦))
10 eqid 2736 . . . 4 ( I ↾ (𝐹𝐴)) = ( I ↾ (𝐹𝐴))
118, 9, 10fundcmpsurinjimaid 44921 . . 3 (𝐹:𝐴𝐵 → ((𝑦𝐴 ↦ (𝐹𝑦)):𝐴onto→(𝐹𝐴) ∧ ( I ↾ (𝐹𝐴)):(𝐹𝐴)–1-1𝐵𝐹 = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦)))))
1211adantr 482 . 2 ((𝐹:𝐴𝐵𝐴𝑉) → ((𝑦𝐴 ↦ (𝐹𝑦)):𝐴onto→(𝐹𝐴) ∧ ( I ↾ (𝐹𝐴)):(𝐹𝐴)–1-1𝐵𝐹 = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦)))))
13 simp1 1136 . . . . 5 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → 𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)))
14 eqidd 2737 . . . . 5 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → 𝐴 = 𝐴)
15 simp3 1138 . . . . 5 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → 𝑝 = (𝐹𝐴))
1613, 14, 15foeq123d 6739 . . . 4 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → (𝑔:𝐴onto𝑝 ↔ (𝑦𝐴 ↦ (𝐹𝑦)):𝐴onto→(𝐹𝐴)))
17 simpl 484 . . . . . 6 (( = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → = ( I ↾ (𝐹𝐴)))
18 simpr 486 . . . . . 6 (( = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → 𝑝 = (𝐹𝐴))
19 eqidd 2737 . . . . . 6 (( = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → 𝐵 = 𝐵)
2017, 18, 19f1eq123d 6738 . . . . 5 (( = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → (:𝑝1-1𝐵 ↔ ( I ↾ (𝐹𝐴)):(𝐹𝐴)–1-1𝐵))
21203adant1 1130 . . . 4 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → (:𝑝1-1𝐵 ↔ ( I ↾ (𝐹𝐴)):(𝐹𝐴)–1-1𝐵))
22 simpl 484 . . . . . . . 8 (( = ( I ↾ (𝐹𝐴)) ∧ 𝑔 = (𝑦𝐴 ↦ (𝐹𝑦))) → = ( I ↾ (𝐹𝐴)))
23 simpr 486 . . . . . . . 8 (( = ( I ↾ (𝐹𝐴)) ∧ 𝑔 = (𝑦𝐴 ↦ (𝐹𝑦))) → 𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)))
2422, 23coeq12d 5786 . . . . . . 7 (( = ( I ↾ (𝐹𝐴)) ∧ 𝑔 = (𝑦𝐴 ↦ (𝐹𝑦))) → (𝑔) = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦))))
2524ancoms 460 . . . . . 6 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴))) → (𝑔) = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦))))
26253adant3 1132 . . . . 5 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → (𝑔) = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦))))
2726eqeq2d 2747 . . . 4 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → (𝐹 = (𝑔) ↔ 𝐹 = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦)))))
2816, 21, 273anbi123d 1436 . . 3 ((𝑔 = (𝑦𝐴 ↦ (𝐹𝑦)) ∧ = ( I ↾ (𝐹𝐴)) ∧ 𝑝 = (𝐹𝐴)) → ((𝑔:𝐴onto𝑝:𝑝1-1𝐵𝐹 = (𝑔)) ↔ ((𝑦𝐴 ↦ (𝐹𝑦)):𝐴onto→(𝐹𝐴) ∧ ( I ↾ (𝐹𝐴)):(𝐹𝐴)–1-1𝐵𝐹 = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦))))))
2928spc3egv 3547 . 2 (((𝑦𝐴 ↦ (𝐹𝑦)) ∈ V ∧ ( I ↾ (𝐹𝐴)) ∈ V ∧ (𝐹𝐴) ∈ V) → (((𝑦𝐴 ↦ (𝐹𝑦)):𝐴onto→(𝐹𝐴) ∧ ( I ↾ (𝐹𝐴)):(𝐹𝐴)–1-1𝐵𝐹 = (( I ↾ (𝐹𝐴)) ∘ (𝑦𝐴 ↦ (𝐹𝑦)))) → ∃𝑔𝑝(𝑔:𝐴onto𝑝:𝑝1-1𝐵𝐹 = (𝑔))))
307, 12, 29sylc 65 1 ((𝐹:𝐴𝐵𝐴𝑉) → ∃𝑔𝑝(𝑔:𝐴onto𝑝:𝑝1-1𝐵𝐹 = (𝑔)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 205  wa 397  w3a 1087   = wceq 1539  wex 1779  wcel 2104  Vcvv 3437  cmpt 5164   I cid 5499  cres 5602  cima 5603  ccom 5604  Fun wfun 6452  wf 6454  1-1wf1 6455  ontowfo 6456  cfv 6458
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1911  ax-6 1969  ax-7 2009  ax-8 2106  ax-9 2114  ax-10 2135  ax-11 2152  ax-12 2169  ax-ext 2707  ax-rep 5218  ax-sep 5232  ax-nul 5239  ax-pr 5361
This theorem depends on definitions:  df-bi 206  df-an 398  df-or 846  df-3an 1089  df-tru 1542  df-fal 1552  df-ex 1780  df-nf 1784  df-sb 2066  df-mo 2538  df-eu 2567  df-clab 2714  df-cleq 2728  df-clel 2814  df-nfc 2887  df-ne 2942  df-ral 3063  df-rex 3072  df-reu 3286  df-rab 3287  df-v 3439  df-sbc 3722  df-csb 3838  df-dif 3895  df-un 3897  df-in 3899  df-ss 3909  df-nul 4263  df-if 4466  df-sn 4566  df-pr 4568  df-op 4572  df-uni 4845  df-iun 4933  df-br 5082  df-opab 5144  df-mpt 5165  df-id 5500  df-xp 5606  df-rel 5607  df-cnv 5608  df-co 5609  df-dm 5610  df-rn 5611  df-res 5612  df-ima 5613  df-iota 6410  df-fun 6460  df-fn 6461  df-f 6462  df-f1 6463  df-fo 6464  df-f1o 6465  df-fv 6466
This theorem is referenced by: (None)
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