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Theorem sncld 23682
Description: A singleton is closed in a Hausdorff space. (Contributed by NM, 5-Mar-2007.) (Revised by Mario Carneiro, 24-Aug-2015.)
Hypothesis
Ref Expression
t1sep.1 𝑋 = ∪ 𝐽
Assertion
Ref Expression
sncld ((𝐽 ∈ Haus ∧ 𝑃 ∈ 𝑋) → {𝑃} ∈ (Clsd‘𝐽))

Proof of Theorem sncld
StepHypRef Expression
1 haust1 23663 . 2 (𝐽 ∈ Haus → 𝐽 ∈ Fre)
2 t1sep.1 . . 3 𝑋 = ∪ 𝐽
32t1sncld 23637 . 2 ((𝐽 ∈ Fre ∧ 𝑃 ∈ 𝑋) → {𝑃} ∈ (Clsd‘𝐽))
41, 3sylan 592 1 ((𝐽 ∈ Haus ∧ 𝑃 ∈ 𝑋) → {𝑃} ∈ (Clsd‘𝐽))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   → wi 4   ∧ wa 401   = wceq 1570   ∈ wcel 2145  {csn 4584  ∪ cuni 4867  ‘cfv 6537  Clsdccld 23327  Frect1 23618  Hauscha 23619
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2213  ax-ext 2733  ax-sep 5249  ax-nul 5260  ax-pow 5327  ax-pr 5391  ax-un 7749
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-ral 3078  df-rex 3088  df-rab 3414  df-v 3453  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-opab 5168  df-mpt 5187  df-id 5546  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-iota 6493  df-fun 6539  df-fv 6545  df-topgen 17607  df-top 23205  df-topon 23222  df-cld 23330  df-t1 23625  df-haus 23626
This theorem is used by:  tgphaus  24429  cnn0opn  25099  csscld  25563  clsocv  25564  abelth  26761  readvrec2  43392  sncldre  46030  dirkercncflem2  47083
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