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Theorem cnneiima 47935
Description: Given a continuous function, the preimage of a neighborhood is a neighborhood. To be precise, the preimage of a neighborhood of a subset 𝑇 of the codomain of a continuous function is a neighborhood of any subset of the preimage of 𝑇. (Contributed by Zhi Wang, 9-Sep-2024.)
Hypotheses
Ref Expression
cnneiima.1 (𝜑𝐹 ∈ (𝐽 Cn 𝐾))
cnneiima.2 (𝜑𝑁 ∈ ((nei‘𝐾)‘𝑇))
cnneiima.3 (𝜑𝑆 ⊆ (𝐹𝑇))
Assertion
Ref Expression
cnneiima (𝜑 → (𝐹𝑁) ∈ ((nei‘𝐽)‘𝑆))

Proof of Theorem cnneiima
StepHypRef Expression
1 cnneiima.3 . . . 4 (𝜑𝑆 ⊆ (𝐹𝑇))
2 cnneiima.1 . . . . . . 7 (𝜑𝐹 ∈ (𝐽 Cn 𝐾))
3 eqid 2728 . . . . . . . 8 𝐽 = 𝐽
4 eqid 2728 . . . . . . . 8 𝐾 = 𝐾
53, 4cnf 23149 . . . . . . 7 (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐹: 𝐽 𝐾)
62, 5syl 17 . . . . . 6 (𝜑𝐹: 𝐽 𝐾)
76ffund 6726 . . . . 5 (𝜑 → Fun 𝐹)
8 cnneiima.2 . . . . . 6 (𝜑𝑁 ∈ ((nei‘𝐾)‘𝑇))
9 cntop2 23144 . . . . . . . 8 (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐾 ∈ Top)
102, 9syl 17 . . . . . . 7 (𝜑𝐾 ∈ Top)
114neiss2 23004 . . . . . . . 8 ((𝐾 ∈ Top ∧ 𝑁 ∈ ((nei‘𝐾)‘𝑇)) → 𝑇 𝐾)
1210, 8, 11syl2anc 583 . . . . . . 7 (𝜑𝑇 𝐾)
134neii1 23009 . . . . . . . 8 ((𝐾 ∈ Top ∧ 𝑁 ∈ ((nei‘𝐾)‘𝑇)) → 𝑁 𝐾)
1410, 8, 13syl2anc 583 . . . . . . 7 (𝜑𝑁 𝐾)
154neiint 23007 . . . . . . 7 ((𝐾 ∈ Top ∧ 𝑇 𝐾𝑁 𝐾) → (𝑁 ∈ ((nei‘𝐾)‘𝑇) ↔ 𝑇 ⊆ ((int‘𝐾)‘𝑁)))
1610, 12, 14, 15syl3anc 1369 . . . . . 6 (𝜑 → (𝑁 ∈ ((nei‘𝐾)‘𝑇) ↔ 𝑇 ⊆ ((int‘𝐾)‘𝑁)))
178, 16mpbid 231 . . . . 5 (𝜑𝑇 ⊆ ((int‘𝐾)‘𝑁))
18 sspreima 7077 . . . . 5 ((Fun 𝐹𝑇 ⊆ ((int‘𝐾)‘𝑁)) → (𝐹𝑇) ⊆ (𝐹 “ ((int‘𝐾)‘𝑁)))
197, 17, 18syl2anc 583 . . . 4 (𝜑 → (𝐹𝑇) ⊆ (𝐹 “ ((int‘𝐾)‘𝑁)))
201, 19sstrd 3990 . . 3 (𝜑𝑆 ⊆ (𝐹 “ ((int‘𝐾)‘𝑁)))
214cnntri 23174 . . . 4 ((𝐹 ∈ (𝐽 Cn 𝐾) ∧ 𝑁 𝐾) → (𝐹 “ ((int‘𝐾)‘𝑁)) ⊆ ((int‘𝐽)‘(𝐹𝑁)))
222, 14, 21syl2anc 583 . . 3 (𝜑 → (𝐹 “ ((int‘𝐾)‘𝑁)) ⊆ ((int‘𝐽)‘(𝐹𝑁)))
2320, 22sstrd 3990 . 2 (𝜑𝑆 ⊆ ((int‘𝐽)‘(𝐹𝑁)))
24 cntop1 23143 . . . 4 (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐽 ∈ Top)
252, 24syl 17 . . 3 (𝜑𝐽 ∈ Top)
26 sspreima 7077 . . . . . 6 ((Fun 𝐹𝑇 𝐾) → (𝐹𝑇) ⊆ (𝐹 𝐾))
277, 12, 26syl2anc 583 . . . . 5 (𝜑 → (𝐹𝑇) ⊆ (𝐹 𝐾))
28 fimacnv 6745 . . . . . 6 (𝐹: 𝐽 𝐾 → (𝐹 𝐾) = 𝐽)
296, 28syl 17 . . . . 5 (𝜑 → (𝐹 𝐾) = 𝐽)
3027, 29sseqtrd 4020 . . . 4 (𝜑 → (𝐹𝑇) ⊆ 𝐽)
311, 30sstrd 3990 . . 3 (𝜑𝑆 𝐽)
32 sspreima 7077 . . . . 5 ((Fun 𝐹𝑁 𝐾) → (𝐹𝑁) ⊆ (𝐹 𝐾))
337, 14, 32syl2anc 583 . . . 4 (𝜑 → (𝐹𝑁) ⊆ (𝐹 𝐾))
3433, 29sseqtrd 4020 . . 3 (𝜑 → (𝐹𝑁) ⊆ 𝐽)
353neiint 23007 . . 3 ((𝐽 ∈ Top ∧ 𝑆 𝐽 ∧ (𝐹𝑁) ⊆ 𝐽) → ((𝐹𝑁) ∈ ((nei‘𝐽)‘𝑆) ↔ 𝑆 ⊆ ((int‘𝐽)‘(𝐹𝑁))))
3625, 31, 34, 35syl3anc 1369 . 2 (𝜑 → ((𝐹𝑁) ∈ ((nei‘𝐽)‘𝑆) ↔ 𝑆 ⊆ ((int‘𝐽)‘(𝐹𝑁))))
3723, 36mpbird 257 1 (𝜑 → (𝐹𝑁) ∈ ((nei‘𝐽)‘𝑆))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 205   = wceq 1534  wcel 2099  wss 3947   cuni 4908  ccnv 5677  cima 5681  Fun wfun 6542  wf 6544  cfv 6548  (class class class)co 7420  Topctop 22794  intcnt 22920  neicnei 23000   Cn ccn 23127
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1790  ax-4 1804  ax-5 1906  ax-6 1964  ax-7 2004  ax-8 2101  ax-9 2109  ax-10 2130  ax-11 2147  ax-12 2167  ax-ext 2699  ax-rep 5285  ax-sep 5299  ax-nul 5306  ax-pow 5365  ax-pr 5429  ax-un 7740
This theorem depends on definitions:  df-bi 206  df-an 396  df-or 847  df-3an 1087  df-tru 1537  df-fal 1547  df-ex 1775  df-nf 1779  df-sb 2061  df-mo 2530  df-eu 2559  df-clab 2706  df-cleq 2720  df-clel 2806  df-nfc 2881  df-ne 2938  df-ral 3059  df-rex 3068  df-reu 3374  df-rab 3430  df-v 3473  df-sbc 3777  df-csb 3893  df-dif 3950  df-un 3952  df-in 3954  df-ss 3964  df-nul 4324  df-if 4530  df-pw 4605  df-sn 4630  df-pr 4632  df-op 4636  df-uni 4909  df-iun 4998  df-br 5149  df-opab 5211  df-mpt 5232  df-id 5576  df-xp 5684  df-rel 5685  df-cnv 5686  df-co 5687  df-dm 5688  df-rn 5689  df-res 5690  df-ima 5691  df-iota 6500  df-fun 6550  df-fn 6551  df-f 6552  df-f1 6553  df-fo 6554  df-f1o 6555  df-fv 6556  df-ov 7423  df-oprab 7424  df-mpo 7425  df-map 8846  df-top 22795  df-topon 22812  df-ntr 22923  df-nei 23001  df-cn 23130
This theorem is referenced by:  sepfsepc  47946
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