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Theorem kur14lem6 30954
 Description: Lemma for kur14 30959. If 𝑘 is the complementation operator and 𝑘 is the closure operator, this expresses the identity 𝑘𝑐𝑘𝐴 = 𝑘𝑐𝑘𝑐𝑘𝑐𝑘𝐴 for any subset 𝐴 of the topological space. This is the key result that lets us cut down long enough sequences of 𝑐𝑘𝑐𝑘... that arise when applying closure and complement repeatedly to 𝐴, and explains why we end up with a number as large as 14, yet no larger. (Contributed by Mario Carneiro, 11-Feb-2015.)
Hypotheses
Ref Expression
kur14lem.j 𝐽 ∈ Top
kur14lem.x 𝑋 = 𝐽
kur14lem.k 𝐾 = (cls‘𝐽)
kur14lem.i 𝐼 = (int‘𝐽)
kur14lem.a 𝐴𝑋
kur14lem.b 𝐵 = (𝑋 ∖ (𝐾𝐴))
Assertion
Ref Expression
kur14lem6 (𝐾‘(𝐼‘(𝐾𝐵))) = (𝐾𝐵)

Proof of Theorem kur14lem6
StepHypRef Expression
1 kur14lem.j . . . . 5 𝐽 ∈ Top
2 kur14lem.x . . . . . 6 𝑋 = 𝐽
3 kur14lem.k . . . . . 6 𝐾 = (cls‘𝐽)
4 kur14lem.i . . . . . 6 𝐼 = (int‘𝐽)
5 kur14lem.b . . . . . . 7 𝐵 = (𝑋 ∖ (𝐾𝐴))
6 difss 3721 . . . . . . 7 (𝑋 ∖ (𝐾𝐴)) ⊆ 𝑋
75, 6eqsstri 3620 . . . . . 6 𝐵𝑋
81, 2, 3, 4, 7kur14lem3 30951 . . . . 5 (𝐾𝐵) ⊆ 𝑋
94fveq1i 6159 . . . . . 6 (𝐼‘(𝐾𝐵)) = ((int‘𝐽)‘(𝐾𝐵))
102ntrss2 20801 . . . . . . 7 ((𝐽 ∈ Top ∧ (𝐾𝐵) ⊆ 𝑋) → ((int‘𝐽)‘(𝐾𝐵)) ⊆ (𝐾𝐵))
111, 8, 10mp2an 707 . . . . . 6 ((int‘𝐽)‘(𝐾𝐵)) ⊆ (𝐾𝐵)
129, 11eqsstri 3620 . . . . 5 (𝐼‘(𝐾𝐵)) ⊆ (𝐾𝐵)
132clsss 20798 . . . . 5 ((𝐽 ∈ Top ∧ (𝐾𝐵) ⊆ 𝑋 ∧ (𝐼‘(𝐾𝐵)) ⊆ (𝐾𝐵)) → ((cls‘𝐽)‘(𝐼‘(𝐾𝐵))) ⊆ ((cls‘𝐽)‘(𝐾𝐵)))
141, 8, 12, 13mp3an 1421 . . . 4 ((cls‘𝐽)‘(𝐼‘(𝐾𝐵))) ⊆ ((cls‘𝐽)‘(𝐾𝐵))
153fveq1i 6159 . . . 4 (𝐾‘(𝐼‘(𝐾𝐵))) = ((cls‘𝐽)‘(𝐼‘(𝐾𝐵)))
163fveq1i 6159 . . . 4 (𝐾‘(𝐾𝐵)) = ((cls‘𝐽)‘(𝐾𝐵))
1714, 15, 163sstr4i 3629 . . 3 (𝐾‘(𝐼‘(𝐾𝐵))) ⊆ (𝐾‘(𝐾𝐵))
181, 2, 3, 4, 7kur14lem5 30953 . . 3 (𝐾‘(𝐾𝐵)) = (𝐾𝐵)
1917, 18sseqtri 3622 . 2 (𝐾‘(𝐼‘(𝐾𝐵))) ⊆ (𝐾𝐵)
201, 2, 3, 4, 8kur14lem2 30950 . . . . 5 (𝐼‘(𝐾𝐵)) = (𝑋 ∖ (𝐾‘(𝑋 ∖ (𝐾𝐵))))
21 difss 3721 . . . . 5 (𝑋 ∖ (𝐾‘(𝑋 ∖ (𝐾𝐵)))) ⊆ 𝑋
2220, 21eqsstri 3620 . . . 4 (𝐼‘(𝐾𝐵)) ⊆ 𝑋
23 kur14lem.a . . . . . . . . 9 𝐴𝑋
241, 2, 3, 4, 23kur14lem3 30951 . . . . . . . 8 (𝐾𝐴) ⊆ 𝑋
255fveq2i 6161 . . . . . . . . . . 11 (𝐾𝐵) = (𝐾‘(𝑋 ∖ (𝐾𝐴)))
2625difeq2i 3709 . . . . . . . . . 10 (𝑋 ∖ (𝐾𝐵)) = (𝑋 ∖ (𝐾‘(𝑋 ∖ (𝐾𝐴))))
271, 2, 3, 4, 24kur14lem2 30950 . . . . . . . . . 10 (𝐼‘(𝐾𝐴)) = (𝑋 ∖ (𝐾‘(𝑋 ∖ (𝐾𝐴))))
284fveq1i 6159 . . . . . . . . . 10 (𝐼‘(𝐾𝐴)) = ((int‘𝐽)‘(𝐾𝐴))
2926, 27, 283eqtr2i 2649 . . . . . . . . 9 (𝑋 ∖ (𝐾𝐵)) = ((int‘𝐽)‘(𝐾𝐴))
302ntrss2 20801 . . . . . . . . . 10 ((𝐽 ∈ Top ∧ (𝐾𝐴) ⊆ 𝑋) → ((int‘𝐽)‘(𝐾𝐴)) ⊆ (𝐾𝐴))
311, 24, 30mp2an 707 . . . . . . . . 9 ((int‘𝐽)‘(𝐾𝐴)) ⊆ (𝐾𝐴)
3229, 31eqsstri 3620 . . . . . . . 8 (𝑋 ∖ (𝐾𝐵)) ⊆ (𝐾𝐴)
332clsss 20798 . . . . . . . 8 ((𝐽 ∈ Top ∧ (𝐾𝐴) ⊆ 𝑋 ∧ (𝑋 ∖ (𝐾𝐵)) ⊆ (𝐾𝐴)) → ((cls‘𝐽)‘(𝑋 ∖ (𝐾𝐵))) ⊆ ((cls‘𝐽)‘(𝐾𝐴)))
341, 24, 32, 33mp3an 1421 . . . . . . 7 ((cls‘𝐽)‘(𝑋 ∖ (𝐾𝐵))) ⊆ ((cls‘𝐽)‘(𝐾𝐴))
353fveq1i 6159 . . . . . . 7 (𝐾‘(𝑋 ∖ (𝐾𝐵))) = ((cls‘𝐽)‘(𝑋 ∖ (𝐾𝐵)))
361, 2, 3, 4, 23kur14lem5 30953 . . . . . . . 8 (𝐾‘(𝐾𝐴)) = (𝐾𝐴)
373fveq1i 6159 . . . . . . . 8 (𝐾‘(𝐾𝐴)) = ((cls‘𝐽)‘(𝐾𝐴))
3836, 37eqtr3i 2645 . . . . . . 7 (𝐾𝐴) = ((cls‘𝐽)‘(𝐾𝐴))
3934, 35, 383sstr4i 3629 . . . . . 6 (𝐾‘(𝑋 ∖ (𝐾𝐵))) ⊆ (𝐾𝐴)
40 sscon 3728 . . . . . 6 ((𝐾‘(𝑋 ∖ (𝐾𝐵))) ⊆ (𝐾𝐴) → (𝑋 ∖ (𝐾𝐴)) ⊆ (𝑋 ∖ (𝐾‘(𝑋 ∖ (𝐾𝐵)))))
4139, 40ax-mp 5 . . . . 5 (𝑋 ∖ (𝐾𝐴)) ⊆ (𝑋 ∖ (𝐾‘(𝑋 ∖ (𝐾𝐵))))
4241, 5, 203sstr4i 3629 . . . 4 𝐵 ⊆ (𝐼‘(𝐾𝐵))
432clsss 20798 . . . 4 ((𝐽 ∈ Top ∧ (𝐼‘(𝐾𝐵)) ⊆ 𝑋𝐵 ⊆ (𝐼‘(𝐾𝐵))) → ((cls‘𝐽)‘𝐵) ⊆ ((cls‘𝐽)‘(𝐼‘(𝐾𝐵))))
441, 22, 42, 43mp3an 1421 . . 3 ((cls‘𝐽)‘𝐵) ⊆ ((cls‘𝐽)‘(𝐼‘(𝐾𝐵)))
453fveq1i 6159 . . 3 (𝐾𝐵) = ((cls‘𝐽)‘𝐵)
4644, 45, 153sstr4i 3629 . 2 (𝐾𝐵) ⊆ (𝐾‘(𝐼‘(𝐾𝐵)))
4719, 46eqssi 3604 1 (𝐾‘(𝐼‘(𝐾𝐵))) = (𝐾𝐵)
 Colors of variables: wff setvar class Syntax hints:   = wceq 1480   ∈ wcel 1987   ∖ cdif 3557   ⊆ wss 3560  ∪ cuni 4409  ‘cfv 5857  Topctop 20638  intcnt 20761  clsccl 20762 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1719  ax-4 1734  ax-5 1836  ax-6 1885  ax-7 1932  ax-8 1989  ax-9 1996  ax-10 2016  ax-11 2031  ax-12 2044  ax-13 2245  ax-ext 2601  ax-rep 4741  ax-sep 4751  ax-nul 4759  ax-pow 4813  ax-pr 4877  ax-un 6914 This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1038  df-tru 1483  df-ex 1702  df-nf 1707  df-sb 1878  df-eu 2473  df-mo 2474  df-clab 2608  df-cleq 2614  df-clel 2617  df-nfc 2750  df-ne 2791  df-ral 2913  df-rex 2914  df-reu 2915  df-rab 2917  df-v 3192  df-sbc 3423  df-csb 3520  df-dif 3563  df-un 3565  df-in 3567  df-ss 3574  df-nul 3898  df-if 4065  df-pw 4138  df-sn 4156  df-pr 4158  df-op 4162  df-uni 4410  df-int 4448  df-iun 4494  df-iin 4495  df-br 4624  df-opab 4684  df-mpt 4685  df-id 4999  df-xp 5090  df-rel 5091  df-cnv 5092  df-co 5093  df-dm 5094  df-rn 5095  df-res 5096  df-ima 5097  df-iota 5820  df-fun 5859  df-fn 5860  df-f 5861  df-f1 5862  df-fo 5863  df-f1o 5864  df-fv 5865  df-top 20639  df-cld 20763  df-ntr 20764  df-cls 20765 This theorem is referenced by:  kur14lem7  30955
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