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Theorem topcld 17104
Description: The underlying set of a topology is closed. Part of Theorem 6.1(1) of [Munkres] p. 93. (Contributed by NM, 3-Oct-2006.)
Hypothesis
Ref Expression
iscld.1  |-  X  = 
U. J
Assertion
Ref Expression
topcld  |-  ( J  e.  Top  ->  X  e.  ( Clsd `  J
) )

Proof of Theorem topcld
StepHypRef Expression
1 difid 3698 . . . 4  |-  ( X 
\  X )  =  (/)
2 0opn 16982 . . . 4  |-  ( J  e.  Top  ->  (/)  e.  J
)
31, 2syl5eqel 2522 . . 3  |-  ( J  e.  Top  ->  ( X  \  X )  e.  J )
4 ssid 3369 . . 3  |-  X  C_  X
53, 4jctil 525 . 2  |-  ( J  e.  Top  ->  ( X  C_  X  /\  ( X  \  X )  e.  J ) )
6 iscld.1 . . 3  |-  X  = 
U. J
76iscld 17096 . 2  |-  ( J  e.  Top  ->  ( X  e.  ( Clsd `  J )  <->  ( X  C_  X  /\  ( X 
\  X )  e.  J ) ) )
85, 7mpbird 225 1  |-  ( J  e.  Top  ->  X  e.  ( Clsd `  J
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 360    = wceq 1653    e. wcel 1726    \ cdif 3319    C_ wss 3322   (/)c0 3630   U.cuni 4017   ` cfv 5457   Topctop 16963   Clsdccld 17085
This theorem is referenced by:  clsval  17106  riincld  17113  clscld  17116  clstop  17138  cldmre  17147  indiscld  17160  iscon2  17482  cnmpt2pc  18958  rlmbn  19320  ubthlem1  22377  unicls  24306  cmpfiiin  26765  kelac1  27152
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1556  ax-5 1567  ax-17 1627  ax-9 1667  ax-8 1688  ax-14 1730  ax-6 1745  ax-7 1750  ax-11 1762  ax-12 1951  ax-ext 2419  ax-sep 4333  ax-nul 4341  ax-pow 4380  ax-pr 4406
This theorem depends on definitions:  df-bi 179  df-or 361  df-an 362  df-3an 939  df-tru 1329  df-ex 1552  df-nf 1555  df-sb 1660  df-eu 2287  df-mo 2288  df-clab 2425  df-cleq 2431  df-clel 2434  df-nfc 2563  df-ne 2603  df-ral 2712  df-rex 2713  df-rab 2716  df-v 2960  df-sbc 3164  df-dif 3325  df-un 3327  df-in 3329  df-ss 3336  df-nul 3631  df-if 3742  df-pw 3803  df-sn 3822  df-pr 3823  df-op 3825  df-uni 4018  df-br 4216  df-opab 4270  df-mpt 4271  df-id 4501  df-xp 4887  df-rel 4888  df-cnv 4889  df-co 4890  df-dm 4891  df-iota 5421  df-fun 5459  df-fv 5465  df-top 16968  df-cld 17088
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