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Theorem dfac9 9148
Description: Equivalence of the axiom of choice with a statement related to ac9 9495; definition AC3 of [Schechter] p. 139. (Contributed by Stefan O'Rear, 22-Feb-2015.)
Assertion
Ref Expression
dfac9 (CHOICE ↔ ∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅))
Distinct variable group:   𝑥,𝑓

Proof of Theorem dfac9
Dummy variables 𝑔 𝑠 𝑡 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 dfac3 9132 . 2 (CHOICE ↔ ∀𝑠𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
2 vex 3341 . . . . . . 7 𝑓 ∈ V
32rnex 7263 . . . . . 6 ran 𝑓 ∈ V
4 raleq 3275 . . . . . . 7 (𝑠 = ran 𝑓 → (∀𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) ↔ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)))
54exbidv 1997 . . . . . 6 (𝑠 = ran 𝑓 → (∃𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) ↔ ∃𝑔𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)))
63, 5spcv 3437 . . . . 5 (∀𝑠𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) → ∃𝑔𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
7 df-nel 3034 . . . . . . . . . . . . . . 15 (∅ ∉ ran 𝑓 ↔ ¬ ∅ ∈ ran 𝑓)
87biimpi 206 . . . . . . . . . . . . . 14 (∅ ∉ ran 𝑓 → ¬ ∅ ∈ ran 𝑓)
98ad2antlr 765 . . . . . . . . . . . . 13 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ 𝑥 ∈ dom 𝑓) → ¬ ∅ ∈ ran 𝑓)
10 fvelrn 6513 . . . . . . . . . . . . . . . 16 ((Fun 𝑓𝑥 ∈ dom 𝑓) → (𝑓𝑥) ∈ ran 𝑓)
1110adantlr 753 . . . . . . . . . . . . . . 15 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ 𝑥 ∈ dom 𝑓) → (𝑓𝑥) ∈ ran 𝑓)
12 eleq1 2825 . . . . . . . . . . . . . . 15 ((𝑓𝑥) = ∅ → ((𝑓𝑥) ∈ ran 𝑓 ↔ ∅ ∈ ran 𝑓))
1311, 12syl5ibcom 235 . . . . . . . . . . . . . 14 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ 𝑥 ∈ dom 𝑓) → ((𝑓𝑥) = ∅ → ∅ ∈ ran 𝑓))
1413necon3bd 2944 . . . . . . . . . . . . 13 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ 𝑥 ∈ dom 𝑓) → (¬ ∅ ∈ ran 𝑓 → (𝑓𝑥) ≠ ∅))
159, 14mpd 15 . . . . . . . . . . . 12 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ 𝑥 ∈ dom 𝑓) → (𝑓𝑥) ≠ ∅)
1615adantlr 753 . . . . . . . . . . 11 ((((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) ∧ 𝑥 ∈ dom 𝑓) → (𝑓𝑥) ≠ ∅)
17 simpll 807 . . . . . . . . . . . . 13 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) → Fun 𝑓)
1817, 10sylan 489 . . . . . . . . . . . 12 ((((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) ∧ 𝑥 ∈ dom 𝑓) → (𝑓𝑥) ∈ ran 𝑓)
19 simplr 809 . . . . . . . . . . . 12 ((((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) ∧ 𝑥 ∈ dom 𝑓) → ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
20 neeq1 2992 . . . . . . . . . . . . . 14 (𝑡 = (𝑓𝑥) → (𝑡 ≠ ∅ ↔ (𝑓𝑥) ≠ ∅))
21 fveq2 6350 . . . . . . . . . . . . . . 15 (𝑡 = (𝑓𝑥) → (𝑔𝑡) = (𝑔‘(𝑓𝑥)))
22 id 22 . . . . . . . . . . . . . . 15 (𝑡 = (𝑓𝑥) → 𝑡 = (𝑓𝑥))
2321, 22eleq12d 2831 . . . . . . . . . . . . . 14 (𝑡 = (𝑓𝑥) → ((𝑔𝑡) ∈ 𝑡 ↔ (𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥)))
2420, 23imbi12d 333 . . . . . . . . . . . . 13 (𝑡 = (𝑓𝑥) → ((𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) ↔ ((𝑓𝑥) ≠ ∅ → (𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥))))
2524rspcva 3445 . . . . . . . . . . . 12 (((𝑓𝑥) ∈ ran 𝑓 ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) → ((𝑓𝑥) ≠ ∅ → (𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥)))
2618, 19, 25syl2anc 696 . . . . . . . . . . 11 ((((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) ∧ 𝑥 ∈ dom 𝑓) → ((𝑓𝑥) ≠ ∅ → (𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥)))
2716, 26mpd 15 . . . . . . . . . 10 ((((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) ∧ 𝑥 ∈ dom 𝑓) → (𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥))
2827ralrimiva 3102 . . . . . . . . 9 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) → ∀𝑥 ∈ dom 𝑓(𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥))
292dmex 7262 . . . . . . . . . 10 dom 𝑓 ∈ V
30 mptelixpg 8109 . . . . . . . . . 10 (dom 𝑓 ∈ V → ((𝑥 ∈ dom 𝑓 ↦ (𝑔‘(𝑓𝑥))) ∈ X𝑥 ∈ dom 𝑓(𝑓𝑥) ↔ ∀𝑥 ∈ dom 𝑓(𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥)))
3129, 30ax-mp 5 . . . . . . . . 9 ((𝑥 ∈ dom 𝑓 ↦ (𝑔‘(𝑓𝑥))) ∈ X𝑥 ∈ dom 𝑓(𝑓𝑥) ↔ ∀𝑥 ∈ dom 𝑓(𝑔‘(𝑓𝑥)) ∈ (𝑓𝑥))
3228, 31sylibr 224 . . . . . . . 8 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) → (𝑥 ∈ dom 𝑓 ↦ (𝑔‘(𝑓𝑥))) ∈ X𝑥 ∈ dom 𝑓(𝑓𝑥))
33 ne0i 4062 . . . . . . . 8 ((𝑥 ∈ dom 𝑓 ↦ (𝑔‘(𝑓𝑥))) ∈ X𝑥 ∈ dom 𝑓(𝑓𝑥) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅)
3432, 33syl 17 . . . . . . 7 (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ∧ ∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅)
3534ex 449 . . . . . 6 ((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → (∀𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅))
3635exlimdv 2008 . . . . 5 ((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → (∃𝑔𝑡 ∈ ran 𝑓(𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅))
376, 36syl5com 31 . . . 4 (∀𝑠𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) → ((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅))
3837alrimiv 2002 . . 3 (∀𝑠𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) → ∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅))
39 fnresi 6167 . . . . . . 7 ( I ↾ (𝑠 ∖ {∅})) Fn (𝑠 ∖ {∅})
40 fnfun 6147 . . . . . . 7 (( I ↾ (𝑠 ∖ {∅})) Fn (𝑠 ∖ {∅}) → Fun ( I ↾ (𝑠 ∖ {∅})))
4139, 40ax-mp 5 . . . . . 6 Fun ( I ↾ (𝑠 ∖ {∅}))
42 neldifsn 4465 . . . . . 6 ¬ ∅ ∈ (𝑠 ∖ {∅})
43 vex 3341 . . . . . . . . 9 𝑠 ∈ V
44 difexg 4958 . . . . . . . . 9 (𝑠 ∈ V → (𝑠 ∖ {∅}) ∈ V)
4543, 44ax-mp 5 . . . . . . . 8 (𝑠 ∖ {∅}) ∈ V
46 resiexg 7265 . . . . . . . 8 ((𝑠 ∖ {∅}) ∈ V → ( I ↾ (𝑠 ∖ {∅})) ∈ V)
4745, 46ax-mp 5 . . . . . . 7 ( I ↾ (𝑠 ∖ {∅})) ∈ V
48 funeq 6067 . . . . . . . . 9 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → (Fun 𝑓 ↔ Fun ( I ↾ (𝑠 ∖ {∅}))))
49 rneq 5504 . . . . . . . . . . . . 13 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → ran 𝑓 = ran ( I ↾ (𝑠 ∖ {∅})))
50 rnresi 5635 . . . . . . . . . . . . 13 ran ( I ↾ (𝑠 ∖ {∅})) = (𝑠 ∖ {∅})
5149, 50syl6eq 2808 . . . . . . . . . . . 12 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → ran 𝑓 = (𝑠 ∖ {∅}))
5251eleq2d 2823 . . . . . . . . . . 11 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → (∅ ∈ ran 𝑓 ↔ ∅ ∈ (𝑠 ∖ {∅})))
5352notbid 307 . . . . . . . . . 10 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → (¬ ∅ ∈ ran 𝑓 ↔ ¬ ∅ ∈ (𝑠 ∖ {∅})))
547, 53syl5bb 272 . . . . . . . . 9 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → (∅ ∉ ran 𝑓 ↔ ¬ ∅ ∈ (𝑠 ∖ {∅})))
5548, 54anbi12d 749 . . . . . . . 8 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → ((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) ↔ (Fun ( I ↾ (𝑠 ∖ {∅})) ∧ ¬ ∅ ∈ (𝑠 ∖ {∅}))))
56 dmeq 5477 . . . . . . . . . . . 12 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → dom 𝑓 = dom ( I ↾ (𝑠 ∖ {∅})))
57 dmresi 5613 . . . . . . . . . . . 12 dom ( I ↾ (𝑠 ∖ {∅})) = (𝑠 ∖ {∅})
5856, 57syl6eq 2808 . . . . . . . . . . 11 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → dom 𝑓 = (𝑠 ∖ {∅}))
5958ixpeq1d 8084 . . . . . . . . . 10 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → X𝑥 ∈ dom 𝑓(𝑓𝑥) = X𝑥 ∈ (𝑠 ∖ {∅})(𝑓𝑥))
60 fveq1 6349 . . . . . . . . . . . 12 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → (𝑓𝑥) = (( I ↾ (𝑠 ∖ {∅}))‘𝑥))
61 fvresi 6601 . . . . . . . . . . . 12 (𝑥 ∈ (𝑠 ∖ {∅}) → (( I ↾ (𝑠 ∖ {∅}))‘𝑥) = 𝑥)
6260, 61sylan9eq 2812 . . . . . . . . . . 11 ((𝑓 = ( I ↾ (𝑠 ∖ {∅})) ∧ 𝑥 ∈ (𝑠 ∖ {∅})) → (𝑓𝑥) = 𝑥)
6362ixpeq2dva 8087 . . . . . . . . . 10 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → X𝑥 ∈ (𝑠 ∖ {∅})(𝑓𝑥) = X𝑥 ∈ (𝑠 ∖ {∅})𝑥)
6459, 63eqtrd 2792 . . . . . . . . 9 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → X𝑥 ∈ dom 𝑓(𝑓𝑥) = X𝑥 ∈ (𝑠 ∖ {∅})𝑥)
6564neeq1d 2989 . . . . . . . 8 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → (X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅ ↔ X𝑥 ∈ (𝑠 ∖ {∅})𝑥 ≠ ∅))
6655, 65imbi12d 333 . . . . . . 7 (𝑓 = ( I ↾ (𝑠 ∖ {∅})) → (((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅) ↔ ((Fun ( I ↾ (𝑠 ∖ {∅})) ∧ ¬ ∅ ∈ (𝑠 ∖ {∅})) → X𝑥 ∈ (𝑠 ∖ {∅})𝑥 ≠ ∅)))
6747, 66spcv 3437 . . . . . 6 (∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅) → ((Fun ( I ↾ (𝑠 ∖ {∅})) ∧ ¬ ∅ ∈ (𝑠 ∖ {∅})) → X𝑥 ∈ (𝑠 ∖ {∅})𝑥 ≠ ∅))
6841, 42, 67mp2ani 716 . . . . 5 (∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅) → X𝑥 ∈ (𝑠 ∖ {∅})𝑥 ≠ ∅)
69 n0 4072 . . . . . 6 (X𝑥 ∈ (𝑠 ∖ {∅})𝑥 ≠ ∅ ↔ ∃𝑔 𝑔X𝑥 ∈ (𝑠 ∖ {∅})𝑥)
70 vex 3341 . . . . . . . . 9 𝑔 ∈ V
7170elixp 8079 . . . . . . . 8 (𝑔X𝑥 ∈ (𝑠 ∖ {∅})𝑥 ↔ (𝑔 Fn (𝑠 ∖ {∅}) ∧ ∀𝑥 ∈ (𝑠 ∖ {∅})(𝑔𝑥) ∈ 𝑥))
72 eldifsn 4460 . . . . . . . . . . . . . 14 (𝑥 ∈ (𝑠 ∖ {∅}) ↔ (𝑥𝑠𝑥 ≠ ∅))
7372imbi1i 338 . . . . . . . . . . . . 13 ((𝑥 ∈ (𝑠 ∖ {∅}) → (𝑔𝑥) ∈ 𝑥) ↔ ((𝑥𝑠𝑥 ≠ ∅) → (𝑔𝑥) ∈ 𝑥))
74 impexp 461 . . . . . . . . . . . . 13 (((𝑥𝑠𝑥 ≠ ∅) → (𝑔𝑥) ∈ 𝑥) ↔ (𝑥𝑠 → (𝑥 ≠ ∅ → (𝑔𝑥) ∈ 𝑥)))
7573, 74bitri 264 . . . . . . . . . . . 12 ((𝑥 ∈ (𝑠 ∖ {∅}) → (𝑔𝑥) ∈ 𝑥) ↔ (𝑥𝑠 → (𝑥 ≠ ∅ → (𝑔𝑥) ∈ 𝑥)))
7675ralbii2 3114 . . . . . . . . . . 11 (∀𝑥 ∈ (𝑠 ∖ {∅})(𝑔𝑥) ∈ 𝑥 ↔ ∀𝑥𝑠 (𝑥 ≠ ∅ → (𝑔𝑥) ∈ 𝑥))
77 neeq1 2992 . . . . . . . . . . . . 13 (𝑥 = 𝑡 → (𝑥 ≠ ∅ ↔ 𝑡 ≠ ∅))
78 fveq2 6350 . . . . . . . . . . . . . 14 (𝑥 = 𝑡 → (𝑔𝑥) = (𝑔𝑡))
79 id 22 . . . . . . . . . . . . . 14 (𝑥 = 𝑡𝑥 = 𝑡)
8078, 79eleq12d 2831 . . . . . . . . . . . . 13 (𝑥 = 𝑡 → ((𝑔𝑥) ∈ 𝑥 ↔ (𝑔𝑡) ∈ 𝑡))
8177, 80imbi12d 333 . . . . . . . . . . . 12 (𝑥 = 𝑡 → ((𝑥 ≠ ∅ → (𝑔𝑥) ∈ 𝑥) ↔ (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡)))
8281cbvralv 3308 . . . . . . . . . . 11 (∀𝑥𝑠 (𝑥 ≠ ∅ → (𝑔𝑥) ∈ 𝑥) ↔ ∀𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
8376, 82bitri 264 . . . . . . . . . 10 (∀𝑥 ∈ (𝑠 ∖ {∅})(𝑔𝑥) ∈ 𝑥 ↔ ∀𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
8483biimpi 206 . . . . . . . . 9 (∀𝑥 ∈ (𝑠 ∖ {∅})(𝑔𝑥) ∈ 𝑥 → ∀𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
8584adantl 473 . . . . . . . 8 ((𝑔 Fn (𝑠 ∖ {∅}) ∧ ∀𝑥 ∈ (𝑠 ∖ {∅})(𝑔𝑥) ∈ 𝑥) → ∀𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
8671, 85sylbi 207 . . . . . . 7 (𝑔X𝑥 ∈ (𝑠 ∖ {∅})𝑥 → ∀𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
8786eximi 1909 . . . . . 6 (∃𝑔 𝑔X𝑥 ∈ (𝑠 ∖ {∅})𝑥 → ∃𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
8869, 87sylbi 207 . . . . 5 (X𝑥 ∈ (𝑠 ∖ {∅})𝑥 ≠ ∅ → ∃𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
8968, 88syl 17 . . . 4 (∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅) → ∃𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
9089alrimiv 2002 . . 3 (∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅) → ∀𝑠𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡))
9138, 90impbii 199 . 2 (∀𝑠𝑔𝑡𝑠 (𝑡 ≠ ∅ → (𝑔𝑡) ∈ 𝑡) ↔ ∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅))
921, 91bitri 264 1 (CHOICE ↔ ∀𝑓((Fun 𝑓 ∧ ∅ ∉ ran 𝑓) → X𝑥 ∈ dom 𝑓(𝑓𝑥) ≠ ∅))
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wb 196  wa 383  wal 1628   = wceq 1630  wex 1851  wcel 2137  wne 2930  wnel 3033  wral 3048  Vcvv 3338  cdif 3710  c0 4056  {csn 4319  cmpt 4879   I cid 5171  dom cdm 5264  ran crn 5265  cres 5266  Fun wfun 6041   Fn wfn 6042  cfv 6047  Xcixp 8072  CHOICEwac 9126
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1869  ax-4 1884  ax-5 1986  ax-6 2052  ax-7 2088  ax-8 2139  ax-9 2146  ax-10 2166  ax-11 2181  ax-12 2194  ax-13 2389  ax-ext 2738  ax-rep 4921  ax-sep 4931  ax-nul 4939  ax-pow 4990  ax-pr 5053  ax-un 7112
This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3an 1074  df-tru 1633  df-ex 1852  df-nf 1857  df-sb 2045  df-eu 2609  df-mo 2610  df-clab 2745  df-cleq 2751  df-clel 2754  df-nfc 2889  df-ne 2931  df-nel 3034  df-ral 3053  df-rex 3054  df-reu 3055  df-rab 3057  df-v 3340  df-sbc 3575  df-csb 3673  df-dif 3716  df-un 3718  df-in 3720  df-ss 3727  df-nul 4057  df-if 4229  df-pw 4302  df-sn 4320  df-pr 4322  df-op 4326  df-uni 4587  df-iun 4672  df-br 4803  df-opab 4863  df-mpt 4880  df-id 5172  df-xp 5270  df-rel 5271  df-cnv 5272  df-co 5273  df-dm 5274  df-rn 5275  df-res 5276  df-ima 5277  df-iota 6010  df-fun 6049  df-fn 6050  df-f 6051  df-f1 6052  df-fo 6053  df-f1o 6054  df-fv 6055  df-ixp 8073  df-ac 9127
This theorem is referenced by:  dfac14  21621  dfac21  38136
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