Theorem intcld 22925

Description: The intersection of a set of closed sets is closed. (Contributed by NM, 5-Oct-2006.)

Assertion

Ref	Expression
intcld	⊢ ((𝐴 ≠ ∅ ∧ 𝐴 ⊆ (Clsd‘𝐽)) → ∩ 𝐴 ∈ (Clsd‘𝐽))

Proof of Theorem intcld

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		intiin 5008	. 2 ⊢ ∩ 𝐴 = ∩ 𝑥 ∈ 𝐴 𝑥
2		dfss3 3924	. . 3 ⊢ (𝐴 ⊆ (Clsd‘𝐽) ↔ ∀𝑥 ∈ 𝐴 𝑥 ∈ (Clsd‘𝐽))
3		iincld 22924	. . 3 ⊢ ((𝐴 ≠ ∅ ∧ ∀𝑥 ∈ 𝐴 𝑥 ∈ (Clsd‘𝐽)) → ∩ 𝑥 ∈ 𝐴 𝑥 ∈ (Clsd‘𝐽))
4	2, 3	sylan2b 594	. 2 ⊢ ((𝐴 ≠ ∅ ∧ 𝐴 ⊆ (Clsd‘𝐽)) → ∩ 𝑥 ∈ 𝐴 𝑥 ∈ (Clsd‘𝐽))
5	1, 4	eqeltrid 2832	1 ⊢ ((𝐴 ≠ ∅ ∧ 𝐴 ⊆ (Clsd‘𝐽)) → ∩ 𝐴 ∈ (Clsd‘𝐽))

Syntax hints:   → wi 4   ∧ wa 395   ∈ wcel 2109   ≠ wne 2925  ∀wral 3044   ⊆ wss 3903  ∅c0 4284  ∩ cint 4896  ∩ ciin 4942  ‘cfv 6482  Clsdccld 22901

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-10 2142  ax-11 2158  ax-12 2178  ax-ext 2701  ax-sep 5235  ax-nul 5245  ax-pow 5304  ax-pr 5371  ax-un 7671

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2066  df-mo 2533  df-eu 2562  df-clab 2708  df-cleq 2721  df-clel 2803  df-nfc 2878  df-ne 2926  df-ral 3045  df-rex 3054  df-rab 3395  df-v 3438  df-dif 3906  df-un 3908  df-in 3910  df-ss 3920  df-nul 4285  df-if 4477  df-pw 4553  df-sn 4578  df-pr 4580  df-op 4584  df-uni 4859  df-int 4897  df-iun 4943  df-iin 4944  df-br 5093  df-opab 5155  df-mpt 5174  df-id 5514  df-xp 5625  df-rel 5626  df-cnv 5627  df-co 5628  df-dm 5629  df-iota 6438  df-fun 6484  df-fn 6485  df-fv 6490  df-top 22779  df-cld 22904

This theorem is referenced by:  incld  22928  clscld  22932  cldmre  22963