Theorem issmfgt 43032

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 483	. . . . . 6 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝑆 ∈ SAlg)
3		simpr 487	. . . . . 6 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐹 ∈ (SMblFn‘𝑆))
4		issmfgt.d	. . . . . 6 ⊢ 𝐷 = dom 𝐹
5	2, 3, 4	smfdmss 43009	. . . . 5 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐷 ⊆ ∪ 𝑆)
6	2, 3, 4	smff 43008	. . . . 5 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐹:𝐷⟶ℝ)
7		nfv 1911	. . . . . . 7 ⊢ Ⅎ𝑏𝜑
8		nfv 1911	. . . . . . 7 ⊢ Ⅎ𝑏 𝐹 ∈ (SMblFn‘𝑆)
9	7, 8	nfan 1896	. . . . . 6 ⊢ Ⅎ𝑏(𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆))
10	2, 5	restuni4 41385	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∪ (𝑆 ↾t 𝐷) = 𝐷)
11	10	eqcomd 2827	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐷 = ∪ (𝑆 ↾t 𝐷))
12	11	rabeqdv 3484	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ 𝑏 < (𝐹‘𝑦)})
13	12	adantr 483	. . . . . . . 8 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ 𝑏 < (𝐹‘𝑦)})
14		nfv 1911	. . . . . . . . . . 11 ⊢ Ⅎ𝑦𝜑
15		nfv 1911	. . . . . . . . . . 11 ⊢ Ⅎ𝑦 𝐹 ∈ (SMblFn‘𝑆)
16	14, 15	nfan 1896	. . . . . . . . . 10 ⊢ Ⅎ𝑦(𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆))
17		nfv 1911	. . . . . . . . . 10 ⊢ Ⅎ𝑦 𝑏 ∈ ℝ
18	16, 17	nfan 1896	. . . . . . . . 9 ⊢ Ⅎ𝑦((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ)
19		nfv 1911	. . . . . . . . 9 ⊢ Ⅎ𝑐((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ)
20	1	uniexd 7467	. . . . . . . . . . . . . 14 ⊢ (𝜑 → ∪ 𝑆 ∈ V)
21	20	adantr 483	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝐷 ⊆ ∪ 𝑆) → ∪ 𝑆 ∈ V)
22		simpr 487	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝐷 ⊆ ∪ 𝑆) → 𝐷 ⊆ ∪ 𝑆)
23	21, 22	ssexd 5227	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝐷 ⊆ ∪ 𝑆) → 𝐷 ∈ V)
24	5, 23	syldan 593	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → 𝐷 ∈ V)
25		eqid 2821	. . . . . . . . . . 11 ⊢ (𝑆 ↾t 𝐷) = (𝑆 ↾t 𝐷)
26	2, 24, 25	subsalsal 42641	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝑆 ↾t 𝐷) ∈ SAlg)
27	26	adantr 483	. . . . . . . . 9 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → (𝑆 ↾t 𝐷) ∈ SAlg)
28		eqid 2821	. . . . . . . . 9 ⊢ ∪ (𝑆 ↾t 𝐷) = ∪ (𝑆 ↾t 𝐷)
29	6	adantr 483	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → 𝐹:𝐷⟶ℝ)
30		simpr 487	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → 𝑦 ∈ ∪ (𝑆 ↾t 𝐷))
31	10	adantr 483	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → ∪ (𝑆 ↾t 𝐷) = 𝐷)
32	30, 31	eleqtrd 2915	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → 𝑦 ∈ 𝐷)
33	29, 32	ffvelrnd 6851	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → (𝐹‘𝑦) ∈ ℝ)
34	33	rexrd 10690	. . . . . . . . . 10 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → (𝐹‘𝑦) ∈ ℝ*)
35	34	adantlr 713	. . . . . . . . 9 ⊢ ((((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) ∧ 𝑦 ∈ ∪ (𝑆 ↾t 𝐷)) → (𝐹‘𝑦) ∈ ℝ*)
36	2, 4	issmfle 43021	. . . . . . . . . . . . . . 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 234	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑐 ∈ ℝ {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷)))
38	37	simp3d 1140	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∀𝑐 ∈ ℝ {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
39	10	rabeqdv 3484	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} = {𝑦 ∈ 𝐷 ∣ (𝐹‘𝑦) ≤ 𝑐})
40	39	eleq1d 2897	. . . . . . . . . . . . . 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 3197	. . . . . . . . . . . . 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 259	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∀𝑐 ∈ ℝ {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
43	42	adantr 483	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑐 ∈ ℝ) → ∀𝑐 ∈ ℝ {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
44		simpr 487	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑐 ∈ ℝ) → 𝑐 ∈ ℝ)
45		rspa 3206	. . . . . . . . . . 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 586	. . . . . . . . . 10 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑐 ∈ ℝ) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
47	46	adantlr 713	. . . . . . . . 9 ⊢ ((((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) ∧ 𝑐 ∈ ℝ) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ (𝐹‘𝑦) ≤ 𝑐} ∈ (𝑆 ↾t 𝐷))
48		simpr 487	. . . . . . . . 9 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → 𝑏 ∈ ℝ)
49	18, 19, 27, 28, 35, 47, 48	salpreimalegt 42987	. . . . . . . 8 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → {𝑦 ∈ ∪ (𝑆 ↾t 𝐷) ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
50	13, 49	eqeltrd 2913	. . . . . . 7 ⊢ (((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) ∧ 𝑏 ∈ ℝ) → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
51	50	ex 415	. . . . . 6 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝑏 ∈ ℝ → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
52	9, 51	ralrimi 3216	. . . . 5 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
53	5, 6, 52	3jca 1124	. . . 4 ⊢ ((𝜑 ∧ 𝐹 ∈ (SMblFn‘𝑆)) → (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
54	53	ex 415	. . 3 ⊢ (𝜑 → (𝐹 ∈ (SMblFn‘𝑆) → (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))))
55		nfv 1911	. . . . . . 7 ⊢ Ⅎ𝑦 𝐷 ⊆ ∪ 𝑆
56		nfv 1911	. . . . . . 7 ⊢ Ⅎ𝑦 𝐹:𝐷⟶ℝ
57		nfcv 2977	. . . . . . . 8 ⊢ Ⅎ𝑦ℝ
58		nfrab1 3384	. . . . . . . . 9 ⊢ Ⅎ𝑦{𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)}
59		nfcv 2977	. . . . . . . . 9 ⊢ Ⅎ𝑦(𝑆 ↾t 𝐷)
60	58, 59	nfel 2992	. . . . . . . 8 ⊢ Ⅎ𝑦{𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)
61	57, 60	nfralw 3225	. . . . . . 7 ⊢ Ⅎ𝑦∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)
62	55, 56, 61	nf3an 1898	. . . . . 6 ⊢ Ⅎ𝑦(𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
63	14, 62	nfan 1896	. . . . 5 ⊢ Ⅎ𝑦(𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
64		nfv 1911	. . . . . . 7 ⊢ Ⅎ𝑏 𝐷 ⊆ ∪ 𝑆
65		nfv 1911	. . . . . . 7 ⊢ Ⅎ𝑏 𝐹:𝐷⟶ℝ
66		nfra1 3219	. . . . . . 7 ⊢ Ⅎ𝑏∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)
67	64, 65, 66	nf3an 1898	. . . . . 6 ⊢ Ⅎ𝑏(𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))
68	7, 67	nfan 1896	. . . . 5 ⊢ Ⅎ𝑏(𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)))
69	1	adantr 483	. . . . 5 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝑆 ∈ SAlg)
70		simpr1 1190	. . . . 5 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝐷 ⊆ ∪ 𝑆)
71		simpr2 1191	. . . . 5 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝐹:𝐷⟶ℝ)
72		simpr3 1192	. . . . 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 43031	. . . 4 ⊢ ((𝜑 ∧ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))) → 𝐹 ∈ (SMblFn‘𝑆))
74	73	ex 415	. . 3 ⊢ (𝜑 → ((𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷)) → 𝐹 ∈ (SMblFn‘𝑆)))
75	54, 74	impbid 214	. 2 ⊢ (𝜑 → (𝐹 ∈ (SMblFn‘𝑆) ↔ (𝐷 ⊆ ∪ 𝑆 ∧ 𝐹:𝐷⟶ℝ ∧ ∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷))))
76		breq1 5068	. . . . . . . 8 ⊢ (𝑏 = 𝑎 → (𝑏 < (𝐹‘𝑦) ↔ 𝑎 < (𝐹‘𝑦)))
77	76	rabbidv 3480	. . . . . . 7 ⊢ (𝑏 = 𝑎 → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑦 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑦)})
78		fveq2 6669	. . . . . . . . . 10 ⊢ (𝑦 = 𝑥 → (𝐹‘𝑦) = (𝐹‘𝑥))
79	78	breq2d 5077	. . . . . . . . 9 ⊢ (𝑦 = 𝑥 → (𝑎 < (𝐹‘𝑦) ↔ 𝑎 < (𝐹‘𝑥)))
80	79	cbvrabv 3491	. . . . . . . 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 2856	. . . . . 6 ⊢ (𝑏 = 𝑎 → {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} = {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)})
83	82	eleq1d 2897	. . . . 5 ⊢ (𝑏 = 𝑎 → ({𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷) ↔ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷)))
84	83	cbvralvw 3449	. . . 4 ⊢ (∀𝑏 ∈ ℝ {𝑦 ∈ 𝐷 ∣ 𝑏 < (𝐹‘𝑦)} ∈ (𝑆 ↾t 𝐷) ↔ ∀𝑎 ∈ ℝ {𝑥 ∈ 𝐷 ∣ 𝑎 < (𝐹‘𝑥)} ∈ (𝑆 ↾t 𝐷))
85	84	3anbi3i 1155	. . 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 281	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 208   ∧ wa 398   ∧ w3a 1083   = wceq 1533   ∈ wcel 2110  ∀wral 3138  {crab 3142  Vcvv 3494   ⊆ wss 3935  ∪ cuni 4837   class class class wbr 5065  dom cdm 5554  ⟶wf 6350  ‘cfv 6354  (class class class)co 7155  ℝcr 10535  ℝ^*cxr 10673   < clt 10674   ≤ cle 10675   ↾_t crest 16693  SAlgcsalg 42592  SMblFncsmblfn 42976

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1792  ax-4 1806  ax-5 1907  ax-6 1966  ax-7 2011  ax-8 2112  ax-9 2120  ax-10 2141  ax-11 2157  ax-12 2173  ax-ext 2793  ax-rep 5189  ax-sep 5202  ax-nul 5209  ax-pow 5265  ax-pr 5329  ax-un 7460  ax-inf2 9103  ax-cc 9856  ax-ac2 9884  ax-cnex 10592  ax-resscn 10593  ax-1cn 10594  ax-icn 10595  ax-addcl 10596  ax-addrcl 10597  ax-mulcl 10598  ax-mulrcl 10599  ax-mulcom 10600  ax-addass 10601  ax-mulass 10602  ax-distr 10603  ax-i2m1 10604  ax-1ne0 10605  ax-1rid 10606  ax-rnegex 10607  ax-rrecex 10608  ax-cnre 10609  ax-pre-lttri 10610  ax-pre-lttrn 10611  ax-pre-ltadd 10612  ax-pre-mulgt0 10613  ax-pre-sup 10614

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3or 1084  df-3an 1085  df-tru 1536  df-ex 1777  df-nf 1781  df-sb 2066  df-mo 2618  df-eu 2650  df-clab 2800  df-cleq 2814  df-clel 2893  df-nfc 2963  df-ne 3017  df-nel 3124  df-ral 3143  df-rex 3144  df-reu 3145  df-rmo 3146  df-rab 3147  df-v 3496  df-sbc 3772  df-csb 3883  df-dif 3938  df-un 3940  df-in 3942  df-ss 3951  df-pss 3953  df-nul 4291  df-if 4467  df-pw 4540  df-sn 4567  df-pr 4569  df-tp 4571  df-op 4573  df-uni 4838  df-int 4876  df-iun 4920  df-iin 4921  df-br 5066  df-opab 5128  df-mpt 5146  df-tr 5172  df-id 5459  df-eprel 5464  df-po 5473  df-so 5474  df-fr 5513  df-se 5514  df-we 5515  df-xp 5560  df-rel 5561  df-cnv 5562  df-co 5563  df-dm 5564  df-rn 5565  df-res 5566  df-ima 5567  df-pred 6147  df-ord 6193  df-on 6194  df-lim 6195  df-suc 6196  df-iota 6313  df-fun 6356  df-fn 6357  df-f 6358  df-f1 6359  df-fo 6360  df-f1o 6361  df-fv 6362  df-isom 6363  df-riota 7113  df-ov 7158  df-oprab 7159  df-mpo 7160  df-om 7580  df-1st 7688  df-2nd 7689  df-wrecs 7946  df-recs 8007  df-rdg 8045  df-1o 8101  df-oadd 8105  df-er 8288  df-map 8407  df-pm 8408  df-en 8509  df-dom 8510  df-sdom 8511  df-fin 8512  df-sup 8905  df-inf 8906  df-card 9367  df-acn 9370  df-ac 9541  df-pnf 10676  df-mnf 10677  df-xr 10678  df-ltxr 10679  df-le 10680  df-sub 10871  df-neg 10872  df-div 11297  df-nn 11638  df-n0 11897  df-z 11981  df-uz 12243  df-q 12348  df-rp 12389  df-ioo 12741  df-ico 12743  df-fl 13161  df-rest 16695  df-salg 42593  df-smblfn 42977

This theorem is referenced by:  issmfgtd  43036  smfpreimagt  43037