Theorem itg2gt0 26082

Description: If the function 𝐹 is strictly positive on a set of positive measure, then the integral of the function is positive. (Contributed by Mario Carneiro, 30-Aug-2014.)

Hypotheses

Ref	Expression
itg2gt0.1	⊢ (𝜑 → 𝐴 ∈ dom vol)
itg2gt0.2	⊢ (𝜑 → 0 < (vol‘𝐴))
itg2gt0.3	⊢ (𝜑 → 𝐹:ℝ⟶(0[,)+∞))
itg2gt0.4	⊢ (𝜑 → 𝐹 ∈ MblFn)
itg2gt0.5	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 0 < (𝐹‘𝑥))

Assertion

Ref	Expression
itg2gt0	⊢ (𝜑 → 0 < (∫2‘𝐹))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐹   𝜑,𝑥

Proof of Theorem itg2gt0

Dummy variables 𝑘 𝑛 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		itg2gt0.2	. 2 ⊢ (𝜑 → 0 < (vol‘𝐴))
2		itg2gt0.1	. . . . . . 7 ⊢ (𝜑 → 𝐴 ∈ dom vol)
3		iccssxr 13562	. . . . . . . 8 ⊢ (0[,]+∞) ⊆ ℝ*
4		volf 25851	. . . . . . . . 9 ⊢ vol:dom vol⟶(0[,]+∞)
5	4	ffvelcdmi 7083	. . . . . . . 8 ⊢ (𝐴 ∈ dom vol → (vol‘𝐴) ∈ (0[,]+∞))
6	3, 5	sselid 3906	. . . . . . 7 ⊢ (𝐴 ∈ dom vol → (vol‘𝐴) ∈ ℝ*)
7	2, 6	syl 18	. . . . . 6 ⊢ (𝜑 → (vol‘𝐴) ∈ ℝ*)
8	7	adantr 486	. . . . 5 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (vol‘𝐴) ∈ ℝ*)
9		itg2gt0.4	. . . . . . . . . . . . . . . 16 ⊢ (𝜑 → 𝐹 ∈ MblFn)
10	9	elexd 3473	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → 𝐹 ∈ V)
11		cnvexg 7936	. . . . . . . . . . . . . . 15 ⊢ (𝐹 ∈ V → ◡𝐹 ∈ V)
12	10, 11	syl 18	. . . . . . . . . . . . . 14 ⊢ (𝜑 → ◡𝐹 ∈ V)
13		imaexg 7925	. . . . . . . . . . . . . 14 ⊢ (◡𝐹 ∈ V → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) ∈ V)
14	12, 13	syl 18	. . . . . . . . . . . . 13 ⊢ (𝜑 → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) ∈ V)
15	14	adantr 486	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝑛 ∈ ℕ) → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) ∈ V)
16	15	fmpttd 7115	. . . . . . . . . . 11 ⊢ (𝜑 → (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))):ℕ⟶V)
17	16	ffnd 6710	. . . . . . . . . 10 ⊢ (𝜑 → (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) Fn ℕ)
18		fniunfv 7251	. . . . . . . . . 10 ⊢ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) Fn ℕ → ∪ 𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) = ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))
19	17, 18	syl 18	. . . . . . . . 9 ⊢ (𝜑 → ∪ 𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) = ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))
20		itg2gt0.3	. . . . . . . . . . . . . . . 16 ⊢ (𝜑 → 𝐹:ℝ⟶(0[,)+∞))
21		rge0ssre 13588	. . . . . . . . . . . . . . . 16 ⊢ (0[,)+∞) ⊆ ℝ
22		fss 6726	. . . . . . . . . . . . . . . 16 ⊢ ((𝐹:ℝ⟶(0[,)+∞) ∧ (0[,)+∞) ⊆ ℝ) → 𝐹:ℝ⟶ℝ)
23	20, 21, 22	sylancl 598	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → 𝐹:ℝ⟶ℝ)
24		mbfima 25952	. . . . . . . . . . . . . . 15 ⊢ ((𝐹 ∈ MblFn ∧ 𝐹:ℝ⟶ℝ) → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) ∈ dom vol)
25	9, 23, 24	syl2anc 596	. . . . . . . . . . . . . 14 ⊢ (𝜑 → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) ∈ dom vol)
26	25	adantr 486	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑛 ∈ ℕ) → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) ∈ dom vol)
27	26	fmpttd 7115	. . . . . . . . . . . 12 ⊢ (𝜑 → (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))):ℕ⟶dom vol)
28	27	ffvelcdmda 7084	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ∈ dom vol)
29	28	ralrimiva 3154	. . . . . . . . . 10 ⊢ (𝜑 → ∀𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ∈ dom vol)
30		iunmbl 25875	. . . . . . . . . 10 ⊢ (∀𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ∈ dom vol → ∪ 𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ∈ dom vol)
31	29, 30	syl 18	. . . . . . . . 9 ⊢ (𝜑 → ∪ 𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ∈ dom vol)
32	19, 31	eqeltrrd 2861	. . . . . . . 8 ⊢ (𝜑 → ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ∈ dom vol)
33		mblss 25853	. . . . . . . 8 ⊢ (∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ∈ dom vol → ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ⊆ ℝ)
34	32, 33	syl 18	. . . . . . 7 ⊢ (𝜑 → ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ⊆ ℝ)
35		ovolcl 25800	. . . . . . 7 ⊢ (∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ⊆ ℝ → (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) ∈ ℝ*)
36	34, 35	syl 18	. . . . . 6 ⊢ (𝜑 → (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) ∈ ℝ*)
37	36	adantr 486	. . . . 5 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) ∈ ℝ*)
38		0xr 11357	. . . . . 6 ⊢ 0 ∈ ℝ*
39	38	a1i 11	. . . . 5 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → 0 ∈ ℝ*)
40		mblvol 25852	. . . . . . . 8 ⊢ (𝐴 ∈ dom vol → (vol‘𝐴) = (vol*‘𝐴))
41	2, 40	syl 18	. . . . . . 7 ⊢ (𝜑 → (vol‘𝐴) = (vol*‘𝐴))
42		mblss 25853	. . . . . . . . . . . . . . . 16 ⊢ (𝐴 ∈ dom vol → 𝐴 ⊆ ℝ)
43	2, 42	syl 18	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → 𝐴 ⊆ ℝ)
44	43	sselda 3908	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 𝑥 ∈ ℝ)
45	20	ffvelcdmda 7084	. . . . . . . . . . . . . . . 16 ⊢ ((𝜑 ∧ 𝑥 ∈ ℝ) → (𝐹‘𝑥) ∈ (0[,)+∞))
46		elrege0 13586	. . . . . . . . . . . . . . . 16 ⊢ ((𝐹‘𝑥) ∈ (0[,)+∞) ↔ ((𝐹‘𝑥) ∈ ℝ ∧ 0 ≤ (𝐹‘𝑥)))
47	45, 46	sylib 221	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑥 ∈ ℝ) → ((𝐹‘𝑥) ∈ ℝ ∧ 0 ≤ (𝐹‘𝑥)))
48	47	simpld 500	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝑥 ∈ ℝ) → (𝐹‘𝑥) ∈ ℝ)
49	44, 48	syldan 603	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (𝐹‘𝑥) ∈ ℝ)
50		itg2gt0.5	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → 0 < (𝐹‘𝑥))
51		nnrecl 12605	. . . . . . . . . . . . 13 ⊢ (((𝐹‘𝑥) ∈ ℝ ∧ 0 < (𝐹‘𝑥)) → ∃𝑘 ∈ ℕ (1 / 𝑘) < (𝐹‘𝑥))
52	49, 50, 51	syl2anc 596	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → ∃𝑘 ∈ ℕ (1 / 𝑘) < (𝐹‘𝑥))
53	20	ffnd 6710	. . . . . . . . . . . . . . . . 17 ⊢ (𝜑 → 𝐹 Fn ℝ)
54	53	ad2antrr 739	. . . . . . . . . . . . . . . 16 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → 𝐹 Fn ℝ)
55		elpreima 7057	. . . . . . . . . . . . . . . 16 ⊢ (𝐹 Fn ℝ → (𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ↔ (𝑥 ∈ ℝ ∧ (𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞))))
56	54, 55	syl 18	. . . . . . . . . . . . . . 15 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → (𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ↔ (𝑥 ∈ ℝ ∧ (𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞))))
57	44	adantr 486	. . . . . . . . . . . . . . . 16 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → 𝑥 ∈ ℝ)
58	57	biantrurd 542	. . . . . . . . . . . . . . 15 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → ((𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞) ↔ (𝑥 ∈ ℝ ∧ (𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞))))
59		nnrecre 12381	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑘 ∈ ℕ → (1 / 𝑘) ∈ ℝ)
60	59	adantl 487	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / 𝑘) ∈ ℝ)
61	60	rexrd 11360	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / 𝑘) ∈ ℝ*)
62	61	adantlr 728	. . . . . . . . . . . . . . . 16 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → (1 / 𝑘) ∈ ℝ*)
63		elioopnf 13575	. . . . . . . . . . . . . . . 16 ⊢ ((1 / 𝑘) ∈ ℝ* → ((𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞) ↔ ((𝐹‘𝑥) ∈ ℝ ∧ (1 / 𝑘) < (𝐹‘𝑥))))
64	62, 63	syl 18	. . . . . . . . . . . . . . 15 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → ((𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞) ↔ ((𝐹‘𝑥) ∈ ℝ ∧ (1 / 𝑘) < (𝐹‘𝑥))))
65	56, 58, 64	3bitr2d 310	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → (𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ↔ ((𝐹‘𝑥) ∈ ℝ ∧ (1 / 𝑘) < (𝐹‘𝑥))))
66		id 23	. . . . . . . . . . . . . . . 16 ⊢ (𝑘 ∈ ℕ → 𝑘 ∈ ℕ)
67		imaexg 7925	. . . . . . . . . . . . . . . . . 18 ⊢ (◡𝐹 ∈ V → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ V)
68	12, 67	syl 18	. . . . . . . . . . . . . . . . 17 ⊢ (𝜑 → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ V)
69	68	adantr 486	. . . . . . . . . . . . . . . 16 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ V)
70		oveq2 7428	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑛 = 𝑘 → (1 / 𝑛) = (1 / 𝑘))
71	70	oveq1d 7435	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑛 = 𝑘 → ((1 / 𝑛)(,)+∞) = ((1 / 𝑘)(,)+∞))
72	71	imaeq2d 6051	. . . . . . . . . . . . . . . . 17 ⊢ (𝑛 = 𝑘 → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) = (◡𝐹 “ ((1 / 𝑘)(,)+∞)))
73		eqid 2760	. . . . . . . . . . . . . . . . 17 ⊢ (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) = (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))
74	72, 73	fvmptg 6991	. . . . . . . . . . . . . . . 16 ⊢ ((𝑘 ∈ ℕ ∧ (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ V) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) = (◡𝐹 “ ((1 / 𝑘)(,)+∞)))
75	66, 69, 74	syl2anr 609	. . . . . . . . . . . . . . 15 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) = (◡𝐹 “ ((1 / 𝑘)(,)+∞)))
76	75	eleq2d 2846	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → (𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ↔ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))))
77	49	adantr 486	. . . . . . . . . . . . . . 15 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → (𝐹‘𝑥) ∈ ℝ)
78	77	biantrurd 542	. . . . . . . . . . . . . 14 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → ((1 / 𝑘) < (𝐹‘𝑥) ↔ ((𝐹‘𝑥) ∈ ℝ ∧ (1 / 𝑘) < (𝐹‘𝑥))))
79	65, 76, 78	3bitr4rd 315	. . . . . . . . . . . . 13 ⊢ (((𝜑 ∧ 𝑥 ∈ 𝐴) ∧ 𝑘 ∈ ℕ) → ((1 / 𝑘) < (𝐹‘𝑥) ↔ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
80	79	rexbidva 3184	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (∃𝑘 ∈ ℕ (1 / 𝑘) < (𝐹‘𝑥) ↔ ∃𝑘 ∈ ℕ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
81	52, 80	mpbid 235	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → ∃𝑘 ∈ ℕ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘))
82	81	ex 418	. . . . . . . . . 10 ⊢ (𝜑 → (𝑥 ∈ 𝐴 → ∃𝑘 ∈ ℕ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
83		eluni2 4870	. . . . . . . . . . 11 ⊢ (𝑥 ∈ ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ↔ ∃𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))𝑥 ∈ 𝑧)
84		eleq2 2849	. . . . . . . . . . . . 13 ⊢ (𝑧 = ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) → (𝑥 ∈ 𝑧 ↔ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
85	84	rexrn 7087	. . . . . . . . . . . 12 ⊢ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) Fn ℕ → (∃𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))𝑥 ∈ 𝑧 ↔ ∃𝑘 ∈ ℕ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
86	17, 85	syl 18	. . . . . . . . . . 11 ⊢ (𝜑 → (∃𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))𝑥 ∈ 𝑧 ↔ ∃𝑘 ∈ ℕ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
87	83, 86	bitrid 286	. . . . . . . . . 10 ⊢ (𝜑 → (𝑥 ∈ ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ↔ ∃𝑘 ∈ ℕ 𝑥 ∈ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
88	82, 87	sylibrd 262	. . . . . . . . 9 ⊢ (𝜑 → (𝑥 ∈ 𝐴 → 𝑥 ∈ ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))))
89	88	ssrdv 3914	. . . . . . . 8 ⊢ (𝜑 → 𝐴 ⊆ ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))
90		ovolss 25807	. . . . . . . 8 ⊢ ((𝐴 ⊆ ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ∧ ∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ⊆ ℝ) → (vol*‘𝐴) ≤ (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))))
91	89, 34, 90	syl2anc 596	. . . . . . 7 ⊢ (𝜑 → (vol*‘𝐴) ≤ (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))))
92	41, 91	eqbrtrd 5126	. . . . . 6 ⊢ (𝜑 → (vol‘𝐴) ≤ (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))))
93	92	adantr 486	. . . . 5 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (vol‘𝐴) ≤ (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))))
94		mblvol 25852	. . . . . . . . 9 ⊢ (∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ∈ dom vol → (vol‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) = (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))))
95	32, 94	syl 18	. . . . . . . 8 ⊢ (𝜑 → (vol‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) = (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))))
96		peano2nn 12348	. . . . . . . . . . . . . . . 16 ⊢ (𝑘 ∈ ℕ → (𝑘 + 1) ∈ ℕ)
97	96	adantl 487	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (𝑘 + 1) ∈ ℕ)
98		nnrecre 12381	. . . . . . . . . . . . . . 15 ⊢ ((𝑘 + 1) ∈ ℕ → (1 / (𝑘 + 1)) ∈ ℝ)
99	97, 98	syl 18	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / (𝑘 + 1)) ∈ ℝ)
100	99	rexrd 11360	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / (𝑘 + 1)) ∈ ℝ*)
101		nnre 12343	. . . . . . . . . . . . . . . 16 ⊢ (𝑘 ∈ ℕ → 𝑘 ∈ ℝ)
102	101	adantl 487	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → 𝑘 ∈ ℝ)
103	102	lep1d 12249	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → 𝑘 ≤ (𝑘 + 1))
104		nngt0 12370	. . . . . . . . . . . . . . . 16 ⊢ (𝑘 ∈ ℕ → 0 < 𝑘)
105	104	adantl 487	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → 0 < 𝑘)
106	97	nnred 12351	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (𝑘 + 1) ∈ ℝ)
107	97	nngt0d 12388	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → 0 < (𝑘 + 1))
108		lerec 12201	. . . . . . . . . . . . . . 15 ⊢ (((𝑘 ∈ ℝ ∧ 0 < 𝑘) ∧ ((𝑘 + 1) ∈ ℝ ∧ 0 < (𝑘 + 1))) → (𝑘 ≤ (𝑘 + 1) ↔ (1 / (𝑘 + 1)) ≤ (1 / 𝑘)))
109	102, 105, 106, 107, 108	syl22anc 852	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (𝑘 ≤ (𝑘 + 1) ↔ (1 / (𝑘 + 1)) ≤ (1 / 𝑘)))
110	103, 109	mpbid 235	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / (𝑘 + 1)) ≤ (1 / 𝑘))
111		iooss1 13512	. . . . . . . . . . . . 13 ⊢ (((1 / (𝑘 + 1)) ∈ ℝ* ∧ (1 / (𝑘 + 1)) ≤ (1 / 𝑘)) → ((1 / 𝑘)(,)+∞) ⊆ ((1 / (𝑘 + 1))(,)+∞))
112	100, 110, 111	syl2anc 596	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → ((1 / 𝑘)(,)+∞) ⊆ ((1 / (𝑘 + 1))(,)+∞))
113		imass2 6054	. . . . . . . . . . . 12 ⊢ (((1 / 𝑘)(,)+∞) ⊆ ((1 / (𝑘 + 1))(,)+∞) → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ⊆ (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)))
114	112, 113	syl 18	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ⊆ (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)))
115	66, 68, 74	syl2anr 609	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) = (◡𝐹 “ ((1 / 𝑘)(,)+∞)))
116		imaexg 7925	. . . . . . . . . . . . 13 ⊢ (◡𝐹 ∈ V → (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)) ∈ V)
117	12, 116	syl 18	. . . . . . . . . . . 12 ⊢ (𝜑 → (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)) ∈ V)
118		oveq2 7428	. . . . . . . . . . . . . . 15 ⊢ (𝑛 = (𝑘 + 1) → (1 / 𝑛) = (1 / (𝑘 + 1)))
119	118	oveq1d 7435	. . . . . . . . . . . . . 14 ⊢ (𝑛 = (𝑘 + 1) → ((1 / 𝑛)(,)+∞) = ((1 / (𝑘 + 1))(,)+∞))
120	119	imaeq2d 6051	. . . . . . . . . . . . 13 ⊢ (𝑛 = (𝑘 + 1) → (◡𝐹 “ ((1 / 𝑛)(,)+∞)) = (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)))
121	120, 73	fvmptg 6991	. . . . . . . . . . . 12 ⊢ (((𝑘 + 1) ∈ ℕ ∧ (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)) ∈ V) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘(𝑘 + 1)) = (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)))
122	96, 117, 121	syl2anr 609	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘(𝑘 + 1)) = (◡𝐹 “ ((1 / (𝑘 + 1))(,)+∞)))
123	114, 115, 122	3sstr4d 3963	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ⊆ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘(𝑘 + 1)))
124	123	ralrimiva 3154	. . . . . . . . 9 ⊢ (𝜑 → ∀𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ⊆ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘(𝑘 + 1)))
125		volsup 25878	. . . . . . . . 9 ⊢ (((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))):ℕ⟶dom vol ∧ ∀𝑘 ∈ ℕ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) ⊆ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘(𝑘 + 1))) → (vol‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) = sup((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))), ℝ*, < ))
126	27, 124, 125	syl2anc 596	. . . . . . . 8 ⊢ (𝜑 → (vol‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) = sup((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))), ℝ*, < ))
127	95, 126	eqtr3d 2797	. . . . . . 7 ⊢ (𝜑 → (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) = sup((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))), ℝ*, < ))
128	127	adantr 486	. . . . . 6 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) = sup((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))), ℝ*, < ))
129	68	adantr 486	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ V)
130	66, 129, 74	syl2anr 609	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) ∧ 𝑘 ∈ ℕ) → ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) = (◡𝐹 “ ((1 / 𝑘)(,)+∞)))
131	130	fveq2d 6889	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) ∧ 𝑘 ∈ ℕ) → (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)) = (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))
132	38	a1i 11	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → 0 ∈ ℝ*)
133		nnrecgt0 12382	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (𝑘 ∈ ℕ → 0 < (1 / 𝑘))
134	133	adantl 487	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → 0 < (1 / 𝑘))
135		0re 11311	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ 0 ∈ ℝ
136		ltle 11399	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ ((0 ∈ ℝ ∧ (1 / 𝑘) ∈ ℝ) → (0 < (1 / 𝑘) → 0 ≤ (1 / 𝑘)))
137	135, 60, 136	sylancr 599	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (0 < (1 / 𝑘) → 0 ≤ (1 / 𝑘)))
138	134, 137	mpd 16	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → 0 ≤ (1 / 𝑘))
139		elxrge0 13589	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ ((1 / 𝑘) ∈ (0[,]+∞) ↔ ((1 / 𝑘) ∈ ℝ* ∧ 0 ≤ (1 / 𝑘)))
140	61, 138, 139	sylanbrc 595	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / 𝑘) ∈ (0[,]+∞))
141		0e0iccpnf 13591	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ 0 ∈ (0[,]+∞)
142		ifcl 4527	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((1 / 𝑘) ∈ (0[,]+∞) ∧ 0 ∈ (0[,]+∞)) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ∈ (0[,]+∞))
143	140, 141, 142	sylancl 598	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ∈ (0[,]+∞))
144	143	adantr 486	. . . . . . . . . . . . . . . . . . . 20 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ∈ (0[,]+∞))
145	144	fmpttd 7115	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)):ℝ⟶(0[,]+∞))
146	145	adantrr 730	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)):ℝ⟶(0[,]+∞))
147		itg2cl 26054	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)):ℝ⟶(0[,]+∞) → (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∈ ℝ*)
148	146, 147	syl 18	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∈ ℝ*)
149		icossicc 13568	. . . . . . . . . . . . . . . . . . . 20 ⊢ (0[,)+∞) ⊆ (0[,]+∞)
150		fss 6726	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝐹:ℝ⟶(0[,)+∞) ∧ (0[,)+∞) ⊆ (0[,]+∞)) → 𝐹:ℝ⟶(0[,]+∞))
151	20, 149, 150	sylancl 598	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝜑 → 𝐹:ℝ⟶(0[,]+∞))
152		itg2cl 26054	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝐹:ℝ⟶(0[,]+∞) → (∫2‘𝐹) ∈ ℝ*)
153	151, 152	syl 18	. . . . . . . . . . . . . . . . . 18 ⊢ (𝜑 → (∫2‘𝐹) ∈ ℝ*)
154	153	adantr 486	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (∫2‘𝐹) ∈ ℝ*)
155		0nrp 13158	. . . . . . . . . . . . . . . . . . 19 ⊢ ¬ 0 ∈ ℝ+
156		simpr 490	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))))
157	115, 28	eqeltrrd 2861	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ dom vol)
158	157	adantrr 730	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ dom vol)
159	158	adantr 486	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ dom vol)
160	156, 135	eqeltrrdi 2869	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∈ ℝ)
161	60, 134	elrpd 13162	. . . . . . . . . . . . . . . . . . . . . . . . . . 27 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / 𝑘) ∈ ℝ+)
162	161	adantrr 730	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (1 / 𝑘) ∈ ℝ+)
163	162	adantr 486	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → (1 / 𝑘) ∈ ℝ+)
164		itg2const2 26063	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ dom vol ∧ (1 / 𝑘) ∈ ℝ+) → ((vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ ↔ (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∈ ℝ))
165	159, 163, 164	syl2anc 596	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → ((vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ ↔ (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∈ ℝ))
166	160, 165	mpbird 260	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ)
167		elrege0 13586	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ ((1 / 𝑘) ∈ (0[,)+∞) ↔ ((1 / 𝑘) ∈ ℝ ∧ 0 ≤ (1 / 𝑘)))
168	60, 138, 167	sylanbrc 595	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (1 / 𝑘) ∈ (0[,)+∞))
169	168	adantrr 730	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (1 / 𝑘) ∈ (0[,)+∞))
170	169	adantr 486	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → (1 / 𝑘) ∈ (0[,)+∞))
171		itg2const 26062	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ dom vol ∧ (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ ∧ (1 / 𝑘) ∈ (0[,)+∞)) → (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) = ((1 / 𝑘) · (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞)))))
172	159, 166, 170, 171	syl3anc 1398	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) = ((1 / 𝑘) · (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞)))))
173	156, 172	eqtrd 2795	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → 0 = ((1 / 𝑘) · (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞)))))
174		simplrr 790	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))
175	166, 174	elrpd 13162	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ+)
176	163, 175	rpmulcld 13181	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → ((1 / 𝑘) · (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞)))) ∈ ℝ+)
177	173, 176	eqeltrd 2860	. . . . . . . . . . . . . . . . . . . 20 ⊢ (((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) ∧ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))) → 0 ∈ ℝ+)
178	177	ex 418	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) → 0 ∈ ℝ+))
179	155, 178	mtoi 202	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → ¬ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))))
180		itg2ge0 26057	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)):ℝ⟶(0[,]+∞) → 0 ≤ (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))))
181	146, 180	syl 18	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → 0 ≤ (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))))
182		xrleloe 13274	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((0 ∈ ℝ* ∧ (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∈ ℝ*) → (0 ≤ (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ↔ (0 < (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∨ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))))))
183	38, 148, 182	sylancr 599	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (0 ≤ (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ↔ (0 < (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∨ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))))))
184	181, 183	mpbid 235	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (0 < (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ∨ 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))))
185	184	ord 878	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (¬ 0 < (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) → 0 = (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))))
186	179, 185	mt3d 149	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → 0 < (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))))
187	151	adantr 486	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → 𝐹:ℝ⟶(0[,]+∞))
188	60	adantr 486	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → (1 / 𝑘) ∈ ℝ)
189	53	adantr 486	. . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → 𝐹 Fn ℝ)
190	189, 55	syl 18	. . . . . . . . . . . . . . . . . . . . . . . . . . . 28 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)) ↔ (𝑥 ∈ ℝ ∧ (𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞))))
191	190	biimpa 482	. . . . . . . . . . . . . . . . . . . . . . . . . . 27 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → (𝑥 ∈ ℝ ∧ (𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞)))
192	191	simpld 500	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → 𝑥 ∈ ℝ)
193	48	adantlr 728	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) → (𝐹‘𝑥) ∈ ℝ)
194	192, 193	syldan 603	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → (𝐹‘𝑥) ∈ ℝ)
195	61	adantr 486	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → (1 / 𝑘) ∈ ℝ*)
196	191	simprd 501	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → (𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞))
197		simpr 490	. . . . . . . . . . . . . . . . . . . . . . . . . . 27 ⊢ (((𝐹‘𝑥) ∈ ℝ ∧ (1 / 𝑘) < (𝐹‘𝑥)) → (1 / 𝑘) < (𝐹‘𝑥))
198	63, 197	biimtrdi 256	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ ((1 / 𝑘) ∈ ℝ* → ((𝐹‘𝑥) ∈ ((1 / 𝑘)(,)+∞) → (1 / 𝑘) < (𝐹‘𝑥)))
199	195, 196, 198	sylc 66	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → (1 / 𝑘) < (𝐹‘𝑥))
200	188, 194, 199	ltled 11459	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → (1 / 𝑘) ≤ (𝐹‘𝑥))
201	47	simprd 501	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ ((𝜑 ∧ 𝑥 ∈ ℝ) → 0 ≤ (𝐹‘𝑥))
202	201	adantlr 728	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) → 0 ≤ (𝐹‘𝑥))
203	192, 202	syldan 603	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → 0 ≤ (𝐹‘𝑥))
204		breq1 5105	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ ((1 / 𝑘) = if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) → ((1 / 𝑘) ≤ (𝐹‘𝑥) ↔ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥)))
205		breq1 5105	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ (0 = if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) → (0 ≤ (𝐹‘𝑥) ↔ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥)))
206	204, 205	ifboth 4521	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (((1 / 𝑘) ≤ (𝐹‘𝑥) ∧ 0 ≤ (𝐹‘𝑥)) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥))
207	200, 203, 206	syl2anc 596	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥))
208	207	adantlr 728	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) ∧ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥))
209		iffalse 4490	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (¬ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) = 0)
210	209	adantl 487	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ ((((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) ∧ ¬ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) = 0)
211	202	adantr 486	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ ((((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) ∧ ¬ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → 0 ≤ (𝐹‘𝑥))
212	210, 211	eqbrtrd 5126	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) ∧ ¬ 𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞))) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥))
213	208, 212	pm2.61dan 825	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ 𝑥 ∈ ℝ) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥))
214	213	ralrimiva 3154	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → ∀𝑥 ∈ ℝ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥))
215	214	adantrr 730	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → ∀𝑥 ∈ ℝ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥))
216		reex 11292	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ℝ ∈ V
217	216	a1i 11	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝜑 → ℝ ∈ V)
218		ovex 7453	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (1 / 𝑘) ∈ V
219		c0ex 11301	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ 0 ∈ V
220	218, 219	ifex 4532	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ∈ V
221	220	a1i 11	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝜑 ∧ 𝑥 ∈ ℝ) → if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ∈ V)
222		fvexd 6900	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝜑 ∧ 𝑥 ∈ ℝ) → (𝐹‘𝑥) ∈ V)
223		eqidd 2761	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝜑 → (𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)) = (𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)))
224	20	feqmptd 6953	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝜑 → 𝐹 = (𝑥 ∈ ℝ ↦ (𝐹‘𝑥)))
225	217, 221, 222, 223, 224	ofrfval2 7714	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝜑 → ((𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)) ∘r ≤ 𝐹 ↔ ∀𝑥 ∈ ℝ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥)))
226	225	biimpar 483	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝜑 ∧ ∀𝑥 ∈ ℝ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0) ≤ (𝐹‘𝑥)) → (𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)) ∘r ≤ 𝐹)
227	215, 226	syldan 603	. . . . . . . . . . . . . . . . . 18 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)) ∘r ≤ 𝐹)
228		itg2le 26061	. . . . . . . . . . . . . . . . . 18 ⊢ (((𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)):ℝ⟶(0[,]+∞) ∧ 𝐹:ℝ⟶(0[,]+∞) ∧ (𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0)) ∘r ≤ 𝐹) → (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ≤ (∫2‘𝐹))
229	146, 187, 227, 228	syl3anc 1398	. . . . . . . . . . . . . . . . 17 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → (∫2‘(𝑥 ∈ ℝ ↦ if(𝑥 ∈ (◡𝐹 “ ((1 / 𝑘)(,)+∞)), (1 / 𝑘), 0))) ≤ (∫2‘𝐹))
230	132, 148, 154, 186, 229	xrltletrd 13291	. . . . . . . . . . . . . . . 16 ⊢ ((𝜑 ∧ (𝑘 ∈ ℕ ∧ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))))) → 0 < (∫2‘𝐹))
231	230	expr 462	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) → 0 < (∫2‘𝐹)))
232	231	con3d 153	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (¬ 0 < (∫2‘𝐹) → ¬ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞)))))
233	4	ffvelcdmi 7083	. . . . . . . . . . . . . . . . 17 ⊢ ((◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ dom vol → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ (0[,]+∞))
234	3, 233	sselid 3906	. . . . . . . . . . . . . . . 16 ⊢ ((◡𝐹 “ ((1 / 𝑘)(,)+∞)) ∈ dom vol → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ*)
235	157, 234	syl 18	. . . . . . . . . . . . . . 15 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ*)
236		xrlenlt 11375	. . . . . . . . . . . . . . 15 ⊢ (((vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ∈ ℝ* ∧ 0 ∈ ℝ*) → ((vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ≤ 0 ↔ ¬ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞)))))
237	235, 38, 236	sylancl 598	. . . . . . . . . . . . . 14 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → ((vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ≤ 0 ↔ ¬ 0 < (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞)))))
238	232, 237	sylibrd 262	. . . . . . . . . . . . 13 ⊢ ((𝜑 ∧ 𝑘 ∈ ℕ) → (¬ 0 < (∫2‘𝐹) → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ≤ 0))
239	238	imp 412	. . . . . . . . . . . 12 ⊢ (((𝜑 ∧ 𝑘 ∈ ℕ) ∧ ¬ 0 < (∫2‘𝐹)) → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ≤ 0)
240	239	an32s 665	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) ∧ 𝑘 ∈ ℕ) → (vol‘(◡𝐹 “ ((1 / 𝑘)(,)+∞))) ≤ 0)
241	131, 240	eqbrtrd 5126	. . . . . . . . . 10 ⊢ (((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) ∧ 𝑘 ∈ ℕ) → (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)) ≤ 0)
242	241	ralrimiva 3154	. . . . . . . . 9 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → ∀𝑘 ∈ ℕ (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)) ≤ 0)
243		ffn 6709	. . . . . . . . . . 11 ⊢ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))):ℕ⟶V → (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) Fn ℕ)
244		fveq2 6885	. . . . . . . . . . . . 13 ⊢ (𝑧 = ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) → (vol‘𝑧) = (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)))
245	244	breq1d 5112	. . . . . . . . . . . 12 ⊢ (𝑧 = ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘) → ((vol‘𝑧) ≤ 0 ↔ (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)) ≤ 0))
246	245	ralrn 7088	. . . . . . . . . . 11 ⊢ ((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) Fn ℕ → (∀𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))(vol‘𝑧) ≤ 0 ↔ ∀𝑘 ∈ ℕ (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)) ≤ 0))
247	16, 243, 246	3syl 19	. . . . . . . . . 10 ⊢ (𝜑 → (∀𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))(vol‘𝑧) ≤ 0 ↔ ∀𝑘 ∈ ℕ (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)) ≤ 0))
248	247	adantr 486	. . . . . . . . 9 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (∀𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))(vol‘𝑧) ≤ 0 ↔ ∀𝑘 ∈ ℕ (vol‘((𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))‘𝑘)) ≤ 0))
249	242, 248	mpbird 260	. . . . . . . 8 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → ∀𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))(vol‘𝑧) ≤ 0)
250		ffn 6709	. . . . . . . . . 10 ⊢ (vol:dom vol⟶(0[,]+∞) → vol Fn dom vol)
251	4, 250	ax-mp 5	. . . . . . . . 9 ⊢ vol Fn dom vol
252	27	frnd 6718	. . . . . . . . . 10 ⊢ (𝜑 → ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ⊆ dom vol)
253	252	adantr 486	. . . . . . . . 9 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ⊆ dom vol)
254		breq1 5105	. . . . . . . . . 10 ⊢ (𝑥 = (vol‘𝑧) → (𝑥 ≤ 0 ↔ (vol‘𝑧) ≤ 0))
255	254	ralima 7243	. . . . . . . . 9 ⊢ ((vol Fn dom vol ∧ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))) ⊆ dom vol) → (∀𝑥 ∈ (vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))𝑥 ≤ 0 ↔ ∀𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))(vol‘𝑧) ≤ 0))
256	251, 253, 255	sylancr 599	. . . . . . . 8 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (∀𝑥 ∈ (vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))𝑥 ≤ 0 ↔ ∀𝑧 ∈ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))(vol‘𝑧) ≤ 0))
257	249, 256	mpbird 260	. . . . . . 7 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → ∀𝑥 ∈ (vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))𝑥 ≤ 0)
258		imassrn 6197	. . . . . . . . 9 ⊢ (vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) ⊆ ran vol
259		frn 6717	. . . . . . . . . . 11 ⊢ (vol:dom vol⟶(0[,]+∞) → ran vol ⊆ (0[,]+∞))
260	4, 259	ax-mp 5	. . . . . . . . . 10 ⊢ ran vol ⊆ (0[,]+∞)
261	260, 3	sstri 3917	. . . . . . . . 9 ⊢ ran vol ⊆ ℝ*
262	258, 261	sstri 3917	. . . . . . . 8 ⊢ (vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) ⊆ ℝ*
263		supxrleub 13457	. . . . . . . 8 ⊢ (((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) ⊆ ℝ* ∧ 0 ∈ ℝ*) → (sup((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))), ℝ*, < ) ≤ 0 ↔ ∀𝑥 ∈ (vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))𝑥 ≤ 0))
264	262, 38, 263	mp2an 705	. . . . . . 7 ⊢ (sup((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))), ℝ*, < ) ≤ 0 ↔ ∀𝑥 ∈ (vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞))))𝑥 ≤ 0)
265	257, 264	sylibr 237	. . . . . 6 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → sup((vol “ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))), ℝ*, < ) ≤ 0)
266	128, 265	eqbrtrd 5126	. . . . 5 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (vol*‘∪ ran (𝑛 ∈ ℕ ↦ (◡𝐹 “ ((1 / 𝑛)(,)+∞)))) ≤ 0)
267	8, 37, 39, 93, 266	xrletrd 13292	. . . 4 ⊢ ((𝜑 ∧ ¬ 0 < (∫2‘𝐹)) → (vol‘𝐴) ≤ 0)
268	267	ex 418	. . 3 ⊢ (𝜑 → (¬ 0 < (∫2‘𝐹) → (vol‘𝐴) ≤ 0))
269		xrlenlt 11375	. . . 4 ⊢ (((vol‘𝐴) ∈ ℝ* ∧ 0 ∈ ℝ*) → ((vol‘𝐴) ≤ 0 ↔ ¬ 0 < (vol‘𝐴)))
270	7, 38, 269	sylancl 598	. . 3 ⊢ (𝜑 → ((vol‘𝐴) ≤ 0 ↔ ¬ 0 < (vol‘𝐴)))
271	268, 270	sylibd 242	. 2 ⊢ (𝜑 → (¬ 0 < (∫2‘𝐹) → ¬ 0 < (vol‘𝐴)))
272	1, 271	mt4d 118	1 ⊢ (𝜑 → 0 < (∫2‘𝐹))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∧ wa 401   ∨ wo 861   = wceq 1569   ∈ wcel 2144  ∀wral 3076  ∃wrex 3086  Vcvv 3450   ⊆ wss 3895  ifcif 4481  ∪ cuni 4866  ∪ ciun 4950   class class class wbr 5102   ↦ cmpt 5185  ^◡ccnv 5649  dom cdm 5650  ran crn 5651   “ cima 5653   Fn wfn 6533  ⟶wf 6534  ‘cfv 6538  (class class class)co 7420   ∘_r cofr 7692  supcsup 9433  ℝcr 11200  0cc0 11201  1c1 11202   + caddc 11204   · cmul 11206  +∞cpnf 11341  ℝ^*cxr 11343   < clt 11344   ≤ cle 11345   / cdiv 11974  ℕcn 12336  ℝ⁺crp 13121  (,)cioo 13477  [,)cico 13479  [,]cicc 13480  vol*covol 25784  volcvol 25785  MblFncmbf 25936  ∫₂citg2 25938

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2212  ax-ext 2732  ax-rep 5231  ax-sep 5248  ax-nul 5259  ax-pow 5326  ax-pr 5390  ax-un 7751  ax-inf2 9643  ax-cc 10514  ax-cnex 11257  ax-resscn 11258  ax-1cn 11259  ax-icn 11260  ax-addcl 11261  ax-addrcl 11262  ax-mulcl 11263  ax-mulrcl 11264  ax-mulcom 11265  ax-addass 11266  ax-mulass 11267  ax-distr 11268  ax-i2m1 11269  ax-1ne0 11270  ax-1rid 11271  ax-rnegex 11272  ax-rrecex 11273  ax-cnre 11274  ax-pre-lttri 11275  ax-pre-lttrn 11276  ax-pre-ltadd 11277  ax-pre-mulgt0 11278  ax-pre-sup 11279  ax-addf 11280

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-nf 1816  df-sb 2099  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-nel 3062  df-ral 3077  df-rex 3087  df-rmo 3365  df-reu 3366  df-rab 3413  df-v 3452  df-sbc 3739  df-csb 3847  df-ss 3896  df-pss 4014  df-dif 4047  df-in 4091  df-un 4151  df-nul 4279  df-if 4482  df-pw 4558  df-sn 4584  df-pr 4586  df-op 4590  df-uni 4867  df-int 4907  df-iun 4952  df-disj 5070  df-br 5103  df-opab 5167  df-mpt 5186  df-tr 5212  df-id 5545  df-eprel 5550  df-po 5558  df-so 5559  df-fr 5603  df-se 5604  df-we 5605  df-xp 5656  df-rel 5657  df-cnv 5658  df-co 5659  df-dm 5660  df-rn 5661  df-res 5662  df-ima 5663  df-pred 6304  df-ord 6365  df-on 6366  df-lim 6367  df-suc 6368  df-iota 6494  df-fun 6540  df-fn 6541  df-f 6542  df-f1 6543  df-fo 6544  df-f1o 6545  df-fv 6546  df-isom 6547  df-riota 7377  df-ov 7423  df-oprab 7424  df-mpo 7425  df-of 7693  df-ofr 7694  df-om 7878  df-1st 8001  df-2nd 8002  df-frecs 8300  df-wrecs 8331  df-recs 8380  df-rdg 8419  df-1o 8477  df-2o 8478  df-er 8718  df-map 8850  df-pm 8851  df-en 8975  df-dom 8976  df-sdom 8977  df-fin 8978  df-fi 9404  df-sup 9435  df-inf 9436  df-oi 9505  df-dju 9983  df-card 10021  df-pnf 11346  df-mnf 11347  df-xr 11348  df-ltxr 11349  df-le 11350  df-sub 11544  df-neg 11545  df-div 11975  df-nn 12337  df-2 12406  df-3 12407  df-n0 12608  df-z 12695  df-uz 12967  df-q 13077  df-rp 13122  df-xneg 13242  df-xadd 13243  df-xmul 13244  df-ioo 13481  df-ico 13483  df-icc 13484  df-fz 13641  df-fzo 13790  df-fl 13933  df-seq 14146  df-exp 14206  df-hash 14476  df-cj 15267  df-re 15268  df-im 15269  df-sqrt 15403  df-abs 15404  df-clim 15656  df-rlim 15657  df-sum 15855  df-rest 17594  df-topgen 17615  df-psmet 21671  df-xmet 21672  df-met 21673  df-bl 21674  df-mopn 21675  df-top 23213  df-topon 23230  df-bases 23265  df-cmp 23706  df-cncf 25200  df-ovol 25786  df-vol 25787  df-mbf 25941  df-itg1 25942  df-itg2 25943  df-0p 25992

This theorem is used by:  itggt0  26165