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Theorem choicefi 38387
 Description: For a finite set, a choice function exists, without using the axiom of choice. (Contributed by Glauco Siliprandi, 24-Dec-2020.)
Hypotheses
Ref Expression
choicefi.a (𝜑𝐴 ∈ Fin)
choicefi.b ((𝜑𝑥𝐴) → 𝐵𝑊)
choicefi.n ((𝜑𝑥𝐴) → 𝐵 ≠ ∅)
Assertion
Ref Expression
choicefi (𝜑 → ∃𝑓(𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵))
Distinct variable groups:   𝐴,𝑓,𝑥   𝐵,𝑓   𝜑,𝑥
Allowed substitution hints:   𝜑(𝑓)   𝐵(𝑥)   𝑊(𝑥,𝑓)

Proof of Theorem choicefi
Dummy variables 𝑔 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 choicefi.a . . . . 5 (𝜑𝐴 ∈ Fin)
2 mptfi 8148 . . . . 5 (𝐴 ∈ Fin → (𝑥𝐴𝐵) ∈ Fin)
31, 2syl 17 . . . 4 (𝜑 → (𝑥𝐴𝐵) ∈ Fin)
4 rnfi 8132 . . . 4 ((𝑥𝐴𝐵) ∈ Fin → ran (𝑥𝐴𝐵) ∈ Fin)
53, 4syl 17 . . 3 (𝜑 → ran (𝑥𝐴𝐵) ∈ Fin)
6 fnchoice 38211 . . 3 (ran (𝑥𝐴𝐵) ∈ Fin → ∃𝑔(𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)))
75, 6syl 17 . 2 (𝜑 → ∃𝑔(𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)))
8 simpl 472 . . . . 5 ((𝜑 ∧ (𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))) → 𝜑)
9 simprl 790 . . . . 5 ((𝜑 ∧ (𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))) → 𝑔 Fn ran (𝑥𝐴𝐵))
10 nfv 1830 . . . . . . . 8 𝑦𝜑
11 nfra1 2925 . . . . . . . 8 𝑦𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)
1210, 11nfan 1816 . . . . . . 7 𝑦(𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))
13 rspa 2914 . . . . . . . . . . . 12 ((∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦) ∧ 𝑦 ∈ ran (𝑥𝐴𝐵)) → (𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))
1413adantll 746 . . . . . . . . . . 11 (((𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) ∧ 𝑦 ∈ ran (𝑥𝐴𝐵)) → (𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))
15 vex 3176 . . . . . . . . . . . . . . . 16 𝑦 ∈ V
16 eqid 2610 . . . . . . . . . . . . . . . . 17 (𝑥𝐴𝐵) = (𝑥𝐴𝐵)
1716elrnmpt 5293 . . . . . . . . . . . . . . . 16 (𝑦 ∈ V → (𝑦 ∈ ran (𝑥𝐴𝐵) ↔ ∃𝑥𝐴 𝑦 = 𝐵))
1815, 17ax-mp 5 . . . . . . . . . . . . . . 15 (𝑦 ∈ ran (𝑥𝐴𝐵) ↔ ∃𝑥𝐴 𝑦 = 𝐵)
1918biimpi 205 . . . . . . . . . . . . . 14 (𝑦 ∈ ran (𝑥𝐴𝐵) → ∃𝑥𝐴 𝑦 = 𝐵)
2019adantl 481 . . . . . . . . . . . . 13 ((𝜑𝑦 ∈ ran (𝑥𝐴𝐵)) → ∃𝑥𝐴 𝑦 = 𝐵)
21 simp3 1056 . . . . . . . . . . . . . . . . 17 ((𝜑𝑥𝐴𝑦 = 𝐵) → 𝑦 = 𝐵)
22 choicefi.n . . . . . . . . . . . . . . . . . 18 ((𝜑𝑥𝐴) → 𝐵 ≠ ∅)
23223adant3 1074 . . . . . . . . . . . . . . . . 17 ((𝜑𝑥𝐴𝑦 = 𝐵) → 𝐵 ≠ ∅)
2421, 23eqnetrd 2849 . . . . . . . . . . . . . . . 16 ((𝜑𝑥𝐴𝑦 = 𝐵) → 𝑦 ≠ ∅)
25243exp 1256 . . . . . . . . . . . . . . 15 (𝜑 → (𝑥𝐴 → (𝑦 = 𝐵𝑦 ≠ ∅)))
2625rexlimdv 3012 . . . . . . . . . . . . . 14 (𝜑 → (∃𝑥𝐴 𝑦 = 𝐵𝑦 ≠ ∅))
2726adantr 480 . . . . . . . . . . . . 13 ((𝜑𝑦 ∈ ran (𝑥𝐴𝐵)) → (∃𝑥𝐴 𝑦 = 𝐵𝑦 ≠ ∅))
2820, 27mpd 15 . . . . . . . . . . . 12 ((𝜑𝑦 ∈ ran (𝑥𝐴𝐵)) → 𝑦 ≠ ∅)
2928adantlr 747 . . . . . . . . . . 11 (((𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) ∧ 𝑦 ∈ ran (𝑥𝐴𝐵)) → 𝑦 ≠ ∅)
30 id 22 . . . . . . . . . . . 12 ((𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦) → (𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))
3130imp 444 . . . . . . . . . . 11 (((𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦) ∧ 𝑦 ≠ ∅) → (𝑔𝑦) ∈ 𝑦)
3214, 29, 31syl2anc 691 . . . . . . . . . 10 (((𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) ∧ 𝑦 ∈ ran (𝑥𝐴𝐵)) → (𝑔𝑦) ∈ 𝑦)
3332ex 449 . . . . . . . . 9 ((𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) → (𝑦 ∈ ran (𝑥𝐴𝐵) → (𝑔𝑦) ∈ 𝑦))
3412, 33ralrimi 2940 . . . . . . . 8 ((𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) → ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦)
35 rsp 2913 . . . . . . . 8 (∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦 → (𝑦 ∈ ran (𝑥𝐴𝐵) → (𝑔𝑦) ∈ 𝑦))
3634, 35syl 17 . . . . . . 7 ((𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) → (𝑦 ∈ ran (𝑥𝐴𝐵) → (𝑔𝑦) ∈ 𝑦))
3712, 36ralrimi 2940 . . . . . 6 ((𝜑 ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) → ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦)
3837adantrl 748 . . . . 5 ((𝜑 ∧ (𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))) → ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦)
39 vex 3176 . . . . . . . . 9 𝑔 ∈ V
4039a1i 11 . . . . . . . 8 (𝜑𝑔 ∈ V)
411mptexd 6391 . . . . . . . 8 (𝜑 → (𝑥𝐴𝐵) ∈ V)
42 coexg 7010 . . . . . . . 8 ((𝑔 ∈ V ∧ (𝑥𝐴𝐵) ∈ V) → (𝑔 ∘ (𝑥𝐴𝐵)) ∈ V)
4340, 41, 42syl2anc 691 . . . . . . 7 (𝜑 → (𝑔 ∘ (𝑥𝐴𝐵)) ∈ V)
44433ad2ant1 1075 . . . . . 6 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) → (𝑔 ∘ (𝑥𝐴𝐵)) ∈ V)
45 simpr 476 . . . . . . . . 9 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵)) → 𝑔 Fn ran (𝑥𝐴𝐵))
46 choicefi.b . . . . . . . . . . . 12 ((𝜑𝑥𝐴) → 𝐵𝑊)
4746ralrimiva 2949 . . . . . . . . . . 11 (𝜑 → ∀𝑥𝐴 𝐵𝑊)
4816fnmpt 5933 . . . . . . . . . . 11 (∀𝑥𝐴 𝐵𝑊 → (𝑥𝐴𝐵) Fn 𝐴)
4947, 48syl 17 . . . . . . . . . 10 (𝜑 → (𝑥𝐴𝐵) Fn 𝐴)
5049adantr 480 . . . . . . . . 9 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵)) → (𝑥𝐴𝐵) Fn 𝐴)
51 ssid 3587 . . . . . . . . . 10 ran (𝑥𝐴𝐵) ⊆ ran (𝑥𝐴𝐵)
5251a1i 11 . . . . . . . . 9 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵)) → ran (𝑥𝐴𝐵) ⊆ ran (𝑥𝐴𝐵))
53 fnco 5913 . . . . . . . . 9 ((𝑔 Fn ran (𝑥𝐴𝐵) ∧ (𝑥𝐴𝐵) Fn 𝐴 ∧ ran (𝑥𝐴𝐵) ⊆ ran (𝑥𝐴𝐵)) → (𝑔 ∘ (𝑥𝐴𝐵)) Fn 𝐴)
5445, 50, 52, 53syl3anc 1318 . . . . . . . 8 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵)) → (𝑔 ∘ (𝑥𝐴𝐵)) Fn 𝐴)
55543adant3 1074 . . . . . . 7 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) → (𝑔 ∘ (𝑥𝐴𝐵)) Fn 𝐴)
56 nfv 1830 . . . . . . . . 9 𝑥𝜑
57 nfcv 2751 . . . . . . . . . 10 𝑥𝑔
58 nfmpt1 4675 . . . . . . . . . . 11 𝑥(𝑥𝐴𝐵)
5958nfrn 5289 . . . . . . . . . 10 𝑥ran (𝑥𝐴𝐵)
6057, 59nffn 5901 . . . . . . . . 9 𝑥 𝑔 Fn ran (𝑥𝐴𝐵)
61 nfv 1830 . . . . . . . . . 10 𝑥(𝑔𝑦) ∈ 𝑦
6259, 61nfral 2929 . . . . . . . . 9 𝑥𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦
6356, 60, 62nf3an 1819 . . . . . . . 8 𝑥(𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦)
64 funmpt 5840 . . . . . . . . . . . . . 14 Fun (𝑥𝐴𝐵)
6564a1i 11 . . . . . . . . . . . . 13 ((𝜑𝑥𝐴) → Fun (𝑥𝐴𝐵))
66 simpr 476 . . . . . . . . . . . . . 14 ((𝜑𝑥𝐴) → 𝑥𝐴)
6716, 46dmmptd 5937 . . . . . . . . . . . . . . . 16 (𝜑 → dom (𝑥𝐴𝐵) = 𝐴)
6867eqcomd 2616 . . . . . . . . . . . . . . 15 (𝜑𝐴 = dom (𝑥𝐴𝐵))
6968adantr 480 . . . . . . . . . . . . . 14 ((𝜑𝑥𝐴) → 𝐴 = dom (𝑥𝐴𝐵))
7066, 69eleqtrd 2690 . . . . . . . . . . . . 13 ((𝜑𝑥𝐴) → 𝑥 ∈ dom (𝑥𝐴𝐵))
71 fvco 6184 . . . . . . . . . . . . 13 ((Fun (𝑥𝐴𝐵) ∧ 𝑥 ∈ dom (𝑥𝐴𝐵)) → ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) = (𝑔‘((𝑥𝐴𝐵)‘𝑥)))
7265, 70, 71syl2anc 691 . . . . . . . . . . . 12 ((𝜑𝑥𝐴) → ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) = (𝑔‘((𝑥𝐴𝐵)‘𝑥)))
7316fvmpt2 6200 . . . . . . . . . . . . . 14 ((𝑥𝐴𝐵𝑊) → ((𝑥𝐴𝐵)‘𝑥) = 𝐵)
7466, 46, 73syl2anc 691 . . . . . . . . . . . . 13 ((𝜑𝑥𝐴) → ((𝑥𝐴𝐵)‘𝑥) = 𝐵)
7574fveq2d 6107 . . . . . . . . . . . 12 ((𝜑𝑥𝐴) → (𝑔‘((𝑥𝐴𝐵)‘𝑥)) = (𝑔𝐵))
7672, 75eqtrd 2644 . . . . . . . . . . 11 ((𝜑𝑥𝐴) → ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) = (𝑔𝐵))
77763ad2antl1 1216 . . . . . . . . . 10 (((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) ∧ 𝑥𝐴) → ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) = (𝑔𝐵))
7816elrnmpt1 5295 . . . . . . . . . . . . 13 ((𝑥𝐴𝐵𝑊) → 𝐵 ∈ ran (𝑥𝐴𝐵))
7966, 46, 78syl2anc 691 . . . . . . . . . . . 12 ((𝜑𝑥𝐴) → 𝐵 ∈ ran (𝑥𝐴𝐵))
80793ad2antl1 1216 . . . . . . . . . . 11 (((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) ∧ 𝑥𝐴) → 𝐵 ∈ ran (𝑥𝐴𝐵))
81 simpl3 1059 . . . . . . . . . . 11 (((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) ∧ 𝑥𝐴) → ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦)
82 fveq2 6103 . . . . . . . . . . . . 13 (𝑦 = 𝐵 → (𝑔𝑦) = (𝑔𝐵))
83 id 22 . . . . . . . . . . . . 13 (𝑦 = 𝐵𝑦 = 𝐵)
8482, 83eleq12d 2682 . . . . . . . . . . . 12 (𝑦 = 𝐵 → ((𝑔𝑦) ∈ 𝑦 ↔ (𝑔𝐵) ∈ 𝐵))
8584rspcva 3280 . . . . . . . . . . 11 ((𝐵 ∈ ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) → (𝑔𝐵) ∈ 𝐵)
8680, 81, 85syl2anc 691 . . . . . . . . . 10 (((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) ∧ 𝑥𝐴) → (𝑔𝐵) ∈ 𝐵)
8777, 86eqeltrd 2688 . . . . . . . . 9 (((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) ∧ 𝑥𝐴) → ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵)
8887ex 449 . . . . . . . 8 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) → (𝑥𝐴 → ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵))
8963, 88ralrimi 2940 . . . . . . 7 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) → ∀𝑥𝐴 ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵)
9055, 89jca 553 . . . . . 6 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) → ((𝑔 ∘ (𝑥𝐴𝐵)) Fn 𝐴 ∧ ∀𝑥𝐴 ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵))
91 fneq1 5893 . . . . . . . 8 (𝑓 = (𝑔 ∘ (𝑥𝐴𝐵)) → (𝑓 Fn 𝐴 ↔ (𝑔 ∘ (𝑥𝐴𝐵)) Fn 𝐴))
92 nfcv 2751 . . . . . . . . . 10 𝑥𝑓
9357, 58nfco 5209 . . . . . . . . . 10 𝑥(𝑔 ∘ (𝑥𝐴𝐵))
9492, 93nfeq 2762 . . . . . . . . 9 𝑥 𝑓 = (𝑔 ∘ (𝑥𝐴𝐵))
95 fveq1 6102 . . . . . . . . . 10 (𝑓 = (𝑔 ∘ (𝑥𝐴𝐵)) → (𝑓𝑥) = ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥))
9695eleq1d 2672 . . . . . . . . 9 (𝑓 = (𝑔 ∘ (𝑥𝐴𝐵)) → ((𝑓𝑥) ∈ 𝐵 ↔ ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵))
9794, 96ralbid 2966 . . . . . . . 8 (𝑓 = (𝑔 ∘ (𝑥𝐴𝐵)) → (∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵 ↔ ∀𝑥𝐴 ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵))
9891, 97anbi12d 743 . . . . . . 7 (𝑓 = (𝑔 ∘ (𝑥𝐴𝐵)) → ((𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵) ↔ ((𝑔 ∘ (𝑥𝐴𝐵)) Fn 𝐴 ∧ ∀𝑥𝐴 ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵)))
9998spcegv 3267 . . . . . 6 ((𝑔 ∘ (𝑥𝐴𝐵)) ∈ V → (((𝑔 ∘ (𝑥𝐴𝐵)) Fn 𝐴 ∧ ∀𝑥𝐴 ((𝑔 ∘ (𝑥𝐴𝐵))‘𝑥) ∈ 𝐵) → ∃𝑓(𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵)))
10044, 90, 99sylc 63 . . . . 5 ((𝜑𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑔𝑦) ∈ 𝑦) → ∃𝑓(𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵))
1018, 9, 38, 100syl3anc 1318 . . . 4 ((𝜑 ∧ (𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦))) → ∃𝑓(𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵))
102101ex 449 . . 3 (𝜑 → ((𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) → ∃𝑓(𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵)))
103102exlimdv 1848 . 2 (𝜑 → (∃𝑔(𝑔 Fn ran (𝑥𝐴𝐵) ∧ ∀𝑦 ∈ ran (𝑥𝐴𝐵)(𝑦 ≠ ∅ → (𝑔𝑦) ∈ 𝑦)) → ∃𝑓(𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵)))
1047, 103mpd 15 1 (𝜑 → ∃𝑓(𝑓 Fn 𝐴 ∧ ∀𝑥𝐴 (𝑓𝑥) ∈ 𝐵))
 Colors of variables: wff setvar class Syntax hints:   → wi 4   ↔ wb 195   ∧ wa 383   ∧ w3a 1031   = wceq 1475  ∃wex 1695   ∈ wcel 1977   ≠ wne 2780  ∀wral 2896  ∃wrex 2897  Vcvv 3173   ⊆ wss 3540  ∅c0 3874   ↦ cmpt 4643  dom cdm 5038  ran crn 5039   ∘ ccom 5042  Fun wfun 5798   Fn wfn 5799  ‘cfv 5804  Fincfn 7841 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-rep 4699  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847 This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3or 1032  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-ral 2901  df-rex 2902  df-reu 2903  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-pss 3556  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-tp 4130  df-op 4132  df-uni 4373  df-int 4411  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-tr 4681  df-eprel 4949  df-id 4953  df-po 4959  df-so 4960  df-fr 4997  df-we 4999  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-pred 5597  df-ord 5643  df-on 5644  df-lim 5645  df-suc 5646  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-ov 6552  df-oprab 6553  df-mpt2 6554  df-om 6958  df-1st 7059  df-2nd 7060  df-wrecs 7294  df-recs 7355  df-rdg 7393  df-1o 7447  df-oadd 7451  df-er 7629  df-en 7842  df-dom 7843  df-fin 7845 This theorem is referenced by:  axccdom  38411  axccd2  38425  qndenserrnbllem  39190  hoiqssbllem3  39514
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