Theorem issmfgt 47206

Description: The predicate "𝐹 is a real-valued measurable function w.r.t. to the sigma-algebra 𝑆". A function is measurable iff the preimages of all left-open intervals unbounded above are in the subspace sigma-algebra induced by its domain. The domain of 𝐹 is required to be b subset of the underlying set of 𝑆. Definition 121C of [Fremlin1] p. 36, and Proposition 121B (iii) of [Fremlin1] p. 35 . (Contributed by Glauco Siliprandi, 26-Jun-2021.)

Hypotheses

Ref	Expression
issmfgt.s	⊢ (𝜑 → 𝑆 ∈ SAlg)
issmfgt.d	⊢ 𝐷 = dom 𝐹

Assertion

Ref	Expression
issmfgt	⊢ (𝜑 → (𝐹 ∈ (SMblFn‘𝑆) ↔ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑎 ∈ ℝ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷))))

Distinct variable groups:   𝐷,𝑎,𝑥   𝐹,𝑎,𝑥   𝑆,𝑎

Allowed substitution hints:   𝜑(𝑥,𝑎)   𝑆(𝑥)

Proof of Theorem issmfgt

Dummy variables 𝑏 𝑦 𝑐 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		issmfgt.s	. . . . . . 7 ⊢ (𝜑 → 𝑆 ∈ SAlg)
2	1	adantr 480	. . . . . 6 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝑆 ∈ SAlg)
3		simpr 484	. . . . . 6 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐹 ∈ (SMblFn‘𝑆))
4		issmfgt.d	. . . . . 6 ⊢ 𝐷 = dom 𝐹
5	2, 3, 4	smfdmss 47183	. . . . 5 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐷 ⊆ ∪ 𝑆)
6	2, 3, 4	smff 47182	. . . . 5 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐹:𝐷⟶ℝ)
7		nfv 1916	. . . . . . 7 ⊢ Ⅎ𝑏𝜑
8		nfv 1916	. . . . . . 7 ⊢ Ⅎ𝑏 𝐹 ∈ (SMblFn‘𝑆)
9	7, 8	nfan 1901	. . . . . 6 ⊢ Ⅎ𝑏(𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆))
10	2, 5	restuni4 45573	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∪ (𝑆 ↾t 𝐷) = 𝐷)
11	10	eqcomd 2743	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐷 = ∪ (𝑆 ↾t 𝐷))
12	11	rabeqdv 3405	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ 𝑏 < (𝐹‘𝑦)})
13	12	adantr 480	. . . . . . . 8 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ 𝑏 < (𝐹‘𝑦)})
14		nfv 1916	. . . . . . . . . . 11 ⊢ Ⅎ𝑦𝜑
15		nfv 1916	. . . . . . . . . . 11 ⊢ Ⅎ𝑦 𝐹 ∈ (SMblFn‘𝑆)
16	14, 15	nfan 1901	. . . . . . . . . 10 ⊢ Ⅎ𝑦(𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆))
17		nfv 1916	. . . . . . . . . 10 ⊢ Ⅎ𝑦 𝑏 ∈ ℝ
18	16, 17	nfan 1901	. . . . . . . . 9 ⊢ Ⅎ𝑦((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ)
19		nfv 1916	. . . . . . . . 9 ⊢ Ⅎ𝑐((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ)
20	1	uniexd 7691	. . . . . . . . . . . . . 14 ⊢ (𝜑 → ∪ 𝑆 ∈ V)
21	20	adantr 480	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝐷 ⊆ ∪ 𝑆) → ∪ 𝑆 ∈ V)
22		simpr 484	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝐷 ⊆ ∪ 𝑆) → 𝐷 ⊆ ∪ 𝑆)
23	21, 22	ssexd 5262	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝐷 ⊆ ∪ 𝑆) → 𝐷 ∈ V)
24	5, 23	syldan 592	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐷 ∈ V)
25		eqid 2737	. . . . . . . . . . 11 ⊢ (𝑆 ↾t 𝐷) = (𝑆 ↾t 𝐷)
26	2, 24, 25	subsalsal 46809	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝑆 ↾t 𝐷) ∈ SAlg)
27	26	adantr 480	. . . . . . . . 9 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → (𝑆 ↾t 𝐷) ∈ SAlg)
28		eqid 2737	. . . . . . . . 9 ⊢ ∪ (𝑆 ↾t 𝐷) = ∪ (𝑆 ↾t 𝐷)
29	6	adantr 480	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → 𝐹:𝐷⟶ℝ)
30		simpr 484	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → 𝑦 ∈ ∪ (𝑆 ↾t 𝐷))
31	10	adantr 480	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → ∪ (𝑆 ↾t 𝐷) = 𝐷)
32	30, 31	eleqtrd 2839	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → 𝑦 ∈ 𝐷)
33	29, 32	ffvelcdmd 7033	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → (𝐹‘𝑦) ∈ ℝ)
34	33	rexrd 11190	. . . . . . . . . 10 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → (𝐹‘𝑦) ∈ ℝ*)
35	34	adantlr 716	. . . . . . . . 9 ⊢ ((((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → (𝐹‘𝑦) ∈ ℝ*)
36	2, 4	issmfle 47195	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝐹 ∈ (SMblFn‘𝑆) ↔ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑐 ∈ ℝ {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))))
37	3, 36	mpbid 232	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑐 ∈ ℝ {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷)))
38	37	simp3d 1145	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∀𝑐 ∈ ℝ {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
39	10	rabeqdv 3405	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} = {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐})
40	39	eleq1d 2822	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ({𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷) ↔ {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷)))
41	40	ralbidv 3161	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (∀𝑐 ∈ ℝ {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷) ↔ ∀𝑐 ∈ ℝ {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷)))
42	38, 41	mpbird 257	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∀𝑐 ∈ ℝ {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
43	42	adantr 480	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑐 ∈ ℝ) → ∀𝑐 ∈ ℝ {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
44		simpr 484	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑐 ∈ ℝ) → 𝑐 ∈ ℝ)
45		rspa 3227	. . . . . . . . . . 11 ⊢ ((∀𝑐 ∈ ℝ {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷) ∧ 𝑐 ∈ ℝ) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
46	43, 44, 45	syl2anc 585	. . . . . . . . . 10 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑐 ∈ ℝ) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
47	46	adantlr 716	. . . . . . . . 9 ⊢ ((((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) ∧ 𝑐 ∈ ℝ) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
48		simpr 484	. . . . . . . . 9 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → 𝑏 ∈ ℝ)
49	18, 19, 27, 28, 35, 47, 48	salpreimalegt 47159	. . . . . . . 8 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
50	13, 49	eqeltrd 2837	. . . . . . 7 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
51	50	ex 412	. . . . . 6 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝑏 ∈ ℝ → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
52	9, 51	ralrimi 3236	. . . . 5 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
53	5, 6, 52	3jca 1129	. . . 4 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
54	53	ex 412	. . 3 ⊢ (𝜑 → (𝐹 ∈ (SMblFn‘𝑆) → (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))))
55		nfv 1916	. . . . . . 7 ⊢ Ⅎ𝑦 𝐷 ⊆ ∪ 𝑆
56		nfv 1916	. . . . . . 7 ⊢ Ⅎ𝑦 𝐹:𝐷⟶ℝ
57		nfcv 2899	. . . . . . . 8 ⊢ Ⅎ𝑦ℝ
58		nfrab1 3410	. . . . . . . . 9 ⊢ Ⅎ𝑦{𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)}
59		nfcv 2899	. . . . . . . . 9 ⊢ Ⅎ𝑦(𝑆 ↾t 𝐷)
60	58, 59	nfel 2914	. . . . . . . 8 ⊢ Ⅎ𝑦{𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)
61	57, 60	nfralw 3285	. . . . . . 7 ⊢ Ⅎ𝑦∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)
62	55, 56, 61	nf3an 1903	. . . . . 6 ⊢ Ⅎ𝑦(𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
63	14, 62	nfan 1901	. . . . 5 ⊢ Ⅎ𝑦(𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
64		nfv 1916	. . . . . . 7 ⊢ Ⅎ𝑏 𝐷 ⊆ ∪ 𝑆
65		nfv 1916	. . . . . . 7 ⊢ Ⅎ𝑏 𝐹:𝐷⟶ℝ
66		nfra1 3262	. . . . . . 7 ⊢ Ⅎ𝑏∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)
67	64, 65, 66	nf3an 1903	. . . . . 6 ⊢ Ⅎ𝑏(𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
68	7, 67	nfan 1901	. . . . 5 ⊢ Ⅎ𝑏(𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
69	1	adantr 480	. . . . 5 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝑆 ∈ SAlg)
70		simpr1 1196	. . . . 5 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝐷 ⊆ ∪ 𝑆)
71		simpr2 1197	. . . . 5 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝐹:𝐷⟶ℝ)
72		simpr3 1198	. . . . 5 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
73	63, 68, 69, 4, 70, 71, 72	issmfgtlem 47205	. . . 4 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝐹 ∈ (SMblFn‘𝑆))
74	73	ex 412	. . 3 ⊢ (𝜑 → ((𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)) → 𝐹 ∈ (SMblFn‘𝑆)))
75	54, 74	impbid 212	. 2 ⊢ (𝜑 → (𝐹 ∈ (SMblFn‘𝑆) ↔ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))))
76		breq1 5089	. . . . . . . 8 ⊢ (𝑏 = 𝑎 → (𝑏 < (𝐹‘𝑦) ↔ 𝑎 < (𝐹‘𝑦)))
77	76	rabbidv 3397	. . . . . . 7 ⊢ (𝑏 = 𝑎 → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑦 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑦)})
78		fveq2 6836	. . . . . . . . . 10 ⊢ (𝑦 = 𝑥 → (𝐹‘𝑦) = (𝐹‘𝑥))
79	78	breq2d 5098	. . . . . . . . 9 ⊢ (𝑦 = 𝑥 → (𝑎 < (𝐹‘𝑦) ↔ 𝑎 < (𝐹‘𝑥)))
80	79	cbvrabv 3400	. . . . . . . 8 ⊢ {𝑦 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑦)} = {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)}
81	80	a1i 11	. . . . . . 7 ⊢ (𝑏 = 𝑎 → {𝑦 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑦)} = {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)})
82	77, 81	eqtrd 2772	. . . . . 6 ⊢ (𝑏 = 𝑎 → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)})
83	82	eleq1d 2822	. . . . 5 ⊢ (𝑏 = 𝑎 → ({𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷) ↔ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷)))
84	83	cbvralvw 3216	. . . 4 ⊢ (∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷) ↔ ∀𝑎 ∈ ℝ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷))
85	84	3anbi3i 1160	. . 3 ⊢ ((𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)) ↔ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑎 ∈ ℝ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷)))
86	85	a1i 11	. 2 ⊢ (𝜑 → ((𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)) ↔ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑎 ∈ ℝ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷))))
87	75, 86	bitrd 279	1 ⊢ (𝜑 → (𝐹 ∈ (SMblFn‘𝑆) ↔ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑎 ∈ ℝ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷))))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   ∧ w3a 1087   = wceq 1542   ∈ wcel 2114  ∀wral 3052  {crab 3390  Vcvv 3430   ⊆ wss 3890  ∪ cuni 4851   class class class wbr 5086  dom cdm 5626  ⟶wf 6490  ‘cfv 6494  (class class class)co 7362  ℝcr 11032  ℝ^*cxr 11173   < clt 11174   ≤ cle 11175   ↾_t crest 17378  SAlgcsalg 46758  SMblFncsmblfn 47145

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 2709  ax-rep 5213  ax-sep 5232  ax-nul 5242  ax-pow 5304  ax-pr 5372  ax-un 7684  ax-inf2 9557  ax-cc 10352  ax-ac2 10380  ax-cnex 11089  ax-resscn 11090  ax-1cn 11091  ax-icn 11092  ax-addcl 11093  ax-addrcl 11094  ax-mulcl 11095  ax-mulrcl 11096  ax-mulcom 11097  ax-addass 11098  ax-mulass 11099  ax-distr 11100  ax-i2m1 11101  ax-1ne0 11102  ax-1rid 11103  ax-rnegex 11104  ax-rrecex 11105  ax-cnre 11106  ax-pre-lttri 11107  ax-pre-lttrn 11108  ax-pre-ltadd 11109  ax-pre-mulgt0 11110  ax-pre-sup 11111

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2540  df-eu 2570  df-clab 2716  df-cleq 2729  df-clel 2812  df-nfc 2886  df-ne 2934  df-nel 3038  df-ral 3053  df-rex 3063  df-rmo 3343  df-reu 3344  df-rab 3391  df-v 3432  df-sbc 3730  df-csb 3839  df-dif 3893  df-un 3895  df-in 3897  df-ss 3907  df-pss 3910  df-nul 4275  df-if 4468  df-pw 4544  df-sn 4569  df-pr 4571  df-op 4575  df-uni 4852  df-int 4891  df-iun 4936  df-iin 4937  df-br 5087  df-opab 5149  df-mpt 5168  df-tr 5194  df-id 5521  df-eprel 5526  df-po 5534  df-so 5535  df-fr 5579  df-se 5580  df-we 5581  df-xp 5632  df-rel 5633  df-cnv 5634  df-co 5635  df-dm 5636  df-rn 5637  df-res 5638  df-ima 5639  df-pred 6261  df-ord 6322  df-on 6323  df-lim 6324  df-suc 6325  df-iota 6450  df-fun 6496  df-fn 6497  df-f 6498  df-f1 6499  df-fo 6500  df-f1o 6501  df-fv 6502  df-isom 6503  df-riota 7319  df-ov 7365  df-oprab 7366  df-mpo 7367  df-om 7813  df-1st 7937  df-2nd 7938  df-frecs 8226  df-wrecs 8257  df-recs 8306  df-rdg 8344  df-1o 8400  df-er 8638  df-map 8770  df-pm 8771  df-en 8889  df-dom 8890  df-sdom 8891  df-fin 8892  df-sup 9350  df-inf 9351  df-card 9858  df-acn 9861  df-ac 10033  df-pnf 11176  df-mnf 11177  df-xr 11178  df-ltxr 11179  df-le 11180  df-sub 11374  df-neg 11375  df-div 11803  df-nn 12170  df-n0 12433  df-z 12520  df-uz 12784  df-q 12894  df-rp 12938  df-ioo 13297  df-ico 13299  df-fl 13746  df-rest 17380  df-salg 46759  df-smblfn 47146

This theorem is referenced by:  issmfgtd  47211  smfpreimagt  47212