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Theorem cnneiima 49305
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 2737 . . . . . . . 8 𝐽 = 𝐽
4 eqid 2737 . . . . . . . 8 𝐾 = 𝐾
53, 4cnf 23207 . . . . . . 7 (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐹: 𝐽 𝐾)
62, 5syl 17 . . . . . 6 (𝜑𝐹: 𝐽 𝐾)
76ffund 6676 . . . . 5 (𝜑 → Fun 𝐹)
8 cnneiima.2 . . . . . 6 (𝜑𝑁 ∈ ((nei‘𝐾)‘𝑇))
9 cntop2 23202 . . . . . . . 8 (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐾 ∈ Top)
102, 9syl 17 . . . . . . 7 (𝜑𝐾 ∈ Top)
114neiss2 23062 . . . . . . . 8 ((𝐾 ∈ Top ∧ 𝑁 ∈ ((nei‘𝐾)‘𝑇)) → 𝑇 𝐾)
1210, 8, 11syl2anc 585 . . . . . . 7 (𝜑𝑇 𝐾)
134neii1 23067 . . . . . . . 8 ((𝐾 ∈ Top ∧ 𝑁 ∈ ((nei‘𝐾)‘𝑇)) → 𝑁 𝐾)
1410, 8, 13syl2anc 585 . . . . . . 7 (𝜑𝑁 𝐾)
154neiint 23065 . . . . . . 7 ((𝐾 ∈ Top ∧ 𝑇 𝐾𝑁 𝐾) → (𝑁 ∈ ((nei‘𝐾)‘𝑇) ↔ 𝑇 ⊆ ((int‘𝐾)‘𝑁)))
1610, 12, 14, 15syl3anc 1374 . . . . . 6 (𝜑 → (𝑁 ∈ ((nei‘𝐾)‘𝑇) ↔ 𝑇 ⊆ ((int‘𝐾)‘𝑁)))
178, 16mpbid 232 . . . . 5 (𝜑𝑇 ⊆ ((int‘𝐾)‘𝑁))
18 sspreima 7024 . . . . 5 ((Fun 𝐹𝑇 ⊆ ((int‘𝐾)‘𝑁)) → (𝐹𝑇) ⊆ (𝐹 “ ((int‘𝐾)‘𝑁)))
197, 17, 18syl2anc 585 . . . 4 (𝜑 → (𝐹𝑇) ⊆ (𝐹 “ ((int‘𝐾)‘𝑁)))
201, 19sstrd 3946 . . 3 (𝜑𝑆 ⊆ (𝐹 “ ((int‘𝐾)‘𝑁)))
214cnntri 23232 . . . 4 ((𝐹 ∈ (𝐽 Cn 𝐾) ∧ 𝑁 𝐾) → (𝐹 “ ((int‘𝐾)‘𝑁)) ⊆ ((int‘𝐽)‘(𝐹𝑁)))
222, 14, 21syl2anc 585 . . 3 (𝜑 → (𝐹 “ ((int‘𝐾)‘𝑁)) ⊆ ((int‘𝐽)‘(𝐹𝑁)))
2320, 22sstrd 3946 . 2 (𝜑𝑆 ⊆ ((int‘𝐽)‘(𝐹𝑁)))
24 cntop1 23201 . . . 4 (𝐹 ∈ (𝐽 Cn 𝐾) → 𝐽 ∈ Top)
252, 24syl 17 . . 3 (𝜑𝐽 ∈ Top)
26 sspreima 7024 . . . . . 6 ((Fun 𝐹𝑇 𝐾) → (𝐹𝑇) ⊆ (𝐹 𝐾))
277, 12, 26syl2anc 585 . . . . 5 (𝜑 → (𝐹𝑇) ⊆ (𝐹 𝐾))
28 fimacnv 6694 . . . . . 6 (𝐹: 𝐽 𝐾 → (𝐹 𝐾) = 𝐽)
296, 28syl 17 . . . . 5 (𝜑 → (𝐹 𝐾) = 𝐽)
3027, 29sseqtrd 3972 . . . 4 (𝜑 → (𝐹𝑇) ⊆ 𝐽)
311, 30sstrd 3946 . . 3 (𝜑𝑆 𝐽)
32 sspreima 7024 . . . . 5 ((Fun 𝐹𝑁 𝐾) → (𝐹𝑁) ⊆ (𝐹 𝐾))
337, 14, 32syl2anc 585 . . . 4 (𝜑 → (𝐹𝑁) ⊆ (𝐹 𝐾))
3433, 29sseqtrd 3972 . . 3 (𝜑 → (𝐹𝑁) ⊆ 𝐽)
353neiint 23065 . . 3 ((𝐽 ∈ Top ∧ 𝑆 𝐽 ∧ (𝐹𝑁) ⊆ 𝐽) → ((𝐹𝑁) ∈ ((nei‘𝐽)‘𝑆) ↔ 𝑆 ⊆ ((int‘𝐽)‘(𝐹𝑁))))
3625, 31, 34, 35syl3anc 1374 . 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 206   = wceq 1542  wcel 2114  wss 3903   cuni 4865  ccnv 5633  cima 5637  Fun wfun 6496  wf 6498  cfv 6502  (class class class)co 7370  Topctop 22854  intcnt 22978  neicnei 23058   Cn ccn 23185
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2709  ax-rep 5226  ax-sep 5245  ax-nul 5255  ax-pow 5314  ax-pr 5381  ax-un 7692
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2540  df-eu 2570  df-clab 2716  df-cleq 2729  df-clel 2812  df-nfc 2886  df-ne 2934  df-ral 3053  df-rex 3063  df-reu 3353  df-rab 3402  df-v 3444  df-sbc 3743  df-csb 3852  df-dif 3906  df-un 3908  df-in 3910  df-ss 3920  df-nul 4288  df-if 4482  df-pw 4558  df-sn 4583  df-pr 4585  df-op 4589  df-uni 4866  df-iun 4950  df-br 5101  df-opab 5163  df-mpt 5182  df-id 5529  df-xp 5640  df-rel 5641  df-cnv 5642  df-co 5643  df-dm 5644  df-rn 5645  df-res 5646  df-ima 5647  df-iota 6458  df-fun 6504  df-fn 6505  df-f 6506  df-f1 6507  df-fo 6508  df-f1o 6509  df-fv 6510  df-ov 7373  df-oprab 7374  df-mpo 7375  df-map 8779  df-top 22855  df-topon 22872  df-ntr 22981  df-nei 23059  df-cn 23188
This theorem is referenced by:  sepfsepc  49316
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