Theorem unisalgen 46768

Description: The union of a set belongs to the sigma-algebra generated by the set. (Contributed by Glauco Siliprandi, 3-Jan-2021.)

Hypotheses

Ref	Expression
unisalgen.x	⊢ (𝜑 → 𝑋 ∈ 𝑉)
unisalgen.s	⊢ 𝑆 = (SalGen‘𝑋)
unisalgen.u	⊢ 𝑈 = ∪ 𝑋

Assertion

Ref	Expression
unisalgen	⊢ (𝜑 → 𝑈 ∈ 𝑆)

Proof of Theorem unisalgen

Step	Hyp	Ref	Expression
1		unisalgen.x	. . . 4 ⊢ (𝜑 → 𝑋 ∈ 𝑉)
2		unisalgen.s	. . . 4 ⊢ 𝑆 = (SalGen‘𝑋)
3		unisalgen.u	. . . 4 ⊢ 𝑈 = ∪ 𝑋
4	1, 2, 3	salgenuni 46765	. . 3 ⊢ (𝜑 → ∪ 𝑆 = 𝑈)
5	4	eqcomd 2742	. 2 ⊢ (𝜑 → 𝑈 = ∪ 𝑆)
6	2	a1i 11	. . . 4 ⊢ (𝜑 → 𝑆 = (SalGen‘𝑋))
7		salgencl 46760	. . . . 5 ⊢ (𝑋 ∈ 𝑉 → (SalGen‘𝑋) ∈ SAlg)
8	1, 7	syl 17	. . . 4 ⊢ (𝜑 → (SalGen‘𝑋) ∈ SAlg)
9	6, 8	eqeltrd 2836	. . 3 ⊢ (𝜑 → 𝑆 ∈ SAlg)
10		saluni 46753	. . 3 ⊢ (𝑆 ∈ SAlg → ∪ 𝑆 ∈ 𝑆)
11	9, 10	syl 17	. 2 ⊢ (𝜑 → ∪ 𝑆 ∈ 𝑆)
12	5, 11	eqeltrd 2836	1 ⊢ (𝜑 → 𝑈 ∈ 𝑆)

Syntax hints:   → wi 4   = wceq 1542   ∈ wcel 2114  ∪ cuni 4850  ‘cfv 6498  SAlgcsalg 46736  SalGencsalgen 46740

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 2708  ax-sep 5231  ax-nul 5241  ax-pow 5307  ax-pr 5375  ax-un 7689

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 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ne 2933  df-ral 3052  df-rex 3062  df-rab 3390  df-v 3431  df-sbc 3729  df-csb 3838  df-dif 3892  df-un 3894  df-in 3896  df-ss 3906  df-nul 4274  df-if 4467  df-pw 4543  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4851  df-int 4890  df-br 5086  df-opab 5148  df-mpt 5167  df-id 5526  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-iota 6454  df-fun 6500  df-fv 6506  df-salg 46737  df-salgen 46741

This theorem is referenced by:  salgensscntex  46772