Theorem rexico 15410

Description: Restrict the base of an upper real quantifier to an upper real set. (Contributed by Mario Carneiro, 12-May-2016.)

Assertion

Ref	Expression
rexico	⊢ ((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) → (∃𝑗 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) ↔ ∃𝑗 ∈ ℝ ∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑)))

Distinct variable groups:   𝑗,𝑘,𝐴   𝐵,𝑗,𝑘   𝜑,𝑗

Allowed substitution hint:   𝜑(𝑘)

Proof of Theorem rexico

Dummy variable 𝑛 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		simpr 489	. . . 4 ⊢ ((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) → 𝐵 ∈ ℝ)
2		pnfxr 11267	. . . 4 ⊢ +∞ ∈ ℝ*
3		icossre 13459	. . . 4 ⊢ ((𝐵 ∈ ℝ ∧ +∞ ∈ ℝ*) → (𝐵[,)+∞) ⊆ ℝ)
4	1, 2, 3	sylancl 597	. . 3 ⊢ ((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) → (𝐵[,)+∞) ⊆ ℝ)
5		ssrexv 4007	. . 3 ⊢ ((𝐵[,)+∞) ⊆ ℝ → (∃𝑗 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) → ∃𝑗 ∈ ℝ ∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑)))
6	4, 5	syl 18	. 2 ⊢ ((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) → (∃𝑗 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) → ∃𝑗 ∈ ℝ ∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑)))
7		simpr 489	. . . . . . 7 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → 𝑗 ∈ ℝ)
8		simplr 780	. . . . . . 7 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → 𝐵 ∈ ℝ)
9	7, 8	ifcld 4534	. . . . . 6 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ∈ ℝ)
10		max1 13215	. . . . . . 7 ⊢ ((𝐵 ∈ ℝ ∧ 𝑗 ∈ ℝ) → 𝐵 ≤ if(𝐵 ≤ 𝑗, 𝑗, 𝐵))
11	10	adantll 726	. . . . . 6 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → 𝐵 ≤ if(𝐵 ≤ 𝑗, 𝑗, 𝐵))
12		elicopnf 13476	. . . . . . 7 ⊢ (𝐵 ∈ ℝ → (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ∈ (𝐵[,)+∞) ↔ (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ∈ ℝ ∧ 𝐵 ≤ if(𝐵 ≤ 𝑗, 𝑗, 𝐵))))
13	12	ad2antlr 739	. . . . . 6 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ∈ (𝐵[,)+∞) ↔ (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ∈ ℝ ∧ 𝐵 ≤ if(𝐵 ≤ 𝑗, 𝑗, 𝐵))))
14	9, 11, 13	mpbir2and 725	. . . . 5 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ∈ (𝐵[,)+∞))
15		simpllr 787	. . . . . . . . 9 ⊢ ((((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) ∧ 𝑘 ∈ 𝐴) → 𝐵 ∈ ℝ)
16		simplr 780	. . . . . . . . 9 ⊢ ((((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) ∧ 𝑘 ∈ 𝐴) → 𝑗 ∈ ℝ)
17		simpll 778	. . . . . . . . . 10 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → 𝐴 ⊆ ℝ)
18	17	sselda 3937	. . . . . . . . 9 ⊢ ((((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) ∧ 𝑘 ∈ 𝐴) → 𝑘 ∈ ℝ)
19		maxle 13221	. . . . . . . . 9 ⊢ ((𝐵 ∈ ℝ ∧ 𝑗 ∈ ℝ ∧ 𝑘 ∈ ℝ) → (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ≤ 𝑘 ↔ (𝐵 ≤ 𝑘 ∧ 𝑗 ≤ 𝑘)))
20	15, 16, 18, 19	syl3anc 1398	. . . . . . . 8 ⊢ ((((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) ∧ 𝑘 ∈ 𝐴) → (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ≤ 𝑘 ↔ (𝐵 ≤ 𝑘 ∧ 𝑗 ≤ 𝑘)))
21		simpr 489	. . . . . . . 8 ⊢ ((𝐵 ≤ 𝑘 ∧ 𝑗 ≤ 𝑘) → 𝑗 ≤ 𝑘)
22	20, 21	biimtrdi 256	. . . . . . 7 ⊢ ((((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) ∧ 𝑘 ∈ 𝐴) → (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ≤ 𝑘 → 𝑗 ≤ 𝑘))
23	22	imim1d 83	. . . . . 6 ⊢ ((((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) ∧ 𝑘 ∈ 𝐴) → ((𝑗 ≤ 𝑘 → 𝜑) → (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ≤ 𝑘 → 𝜑)))
24	23	ralimdva 3177	. . . . 5 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → (∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) → ∀𝑘 ∈ 𝐴 (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ≤ 𝑘 → 𝜑)))
25		breq1 5112	. . . . . 6 ⊢ (𝑛 = if(𝐵 ≤ 𝑗, 𝑗, 𝐵) → (𝑛 ≤ 𝑘 ↔ if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ≤ 𝑘))
26	25	rspceaimv 3587	. . . . 5 ⊢ ((if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ∈ (𝐵[,)+∞) ∧ ∀𝑘 ∈ 𝐴 (if(𝐵 ≤ 𝑗, 𝑗, 𝐵) ≤ 𝑘 → 𝜑)) → ∃𝑛 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑛 ≤ 𝑘 → 𝜑))
27	14, 24, 26	syl6an 696	. . . 4 ⊢ (((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) ∧ 𝑗 ∈ ℝ) → (∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) → ∃𝑛 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑛 ≤ 𝑘 → 𝜑)))
28	27	rexlimdva 3166	. . 3 ⊢ ((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) → (∃𝑗 ∈ ℝ ∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) → ∃𝑛 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑛 ≤ 𝑘 → 𝜑)))
29		breq1 5112	. . . . . 6 ⊢ (𝑛 = 𝑗 → (𝑛 ≤ 𝑘 ↔ 𝑗 ≤ 𝑘))
30	29	imbi1d 344	. . . . 5 ⊢ (𝑛 = 𝑗 → ((𝑛 ≤ 𝑘 → 𝜑) ↔ (𝑗 ≤ 𝑘 → 𝜑)))
31	30	ralbidv 3188	. . . 4 ⊢ (𝑛 = 𝑗 → (∀𝑘 ∈ 𝐴 (𝑛 ≤ 𝑘 → 𝜑) ↔ ∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑)))
32	31	cbvrexvw 3244	. . 3 ⊢ (∃𝑛 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑛 ≤ 𝑘 → 𝜑) ↔ ∃𝑗 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑))
33	28, 32	imbitrdi 254	. 2 ⊢ ((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) → (∃𝑗 ∈ ℝ ∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) → ∃𝑗 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑)))
34	6, 33	impbid 215	1 ⊢ ((𝐴 ⊆ ℝ ∧ 𝐵 ∈ ℝ) → (∃𝑗 ∈ (𝐵[,)+∞)∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑) ↔ ∃𝑗 ∈ ℝ ∀𝑘 ∈ 𝐴 (𝑗 ≤ 𝑘 → 𝜑)))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 400   ∈ wcel 2143  ∀wral 3079  ∃wrex 3089   ⊆ wss 3905  ifcif 4487   class class class wbr 5109  (class class class)co 7410  ℝcr 11103  +∞cpnf 11244  ℝ^*cxr 11246   ≤ cle 11248  [,)cico 13378

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-10 2176  ax-11 2192  ax-12 2213  ax-ext 2735  ax-sep 5257  ax-nul 5269  ax-pow 5336  ax-pr 5404  ax-un 7732  ax-cnex 11160  ax-resscn 11161  ax-pre-lttri 11178  ax-pre-lttrn 11179

This proof depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1810  df-nf 1814  df-sb 2097  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2838  df-nfc 2912  df-ne 2959  df-nel 3065  df-ral 3080  df-rex 3090  df-rab 3417  df-v 3457  df-sbc 3745  df-csb 3854  df-dif 3908  df-un 3910  df-in 3912  df-ss 3922  df-nul 4287  df-if 4488  df-pw 4564  df-sn 4590  df-pr 4592  df-op 4596  df-uni 4873  df-br 5110  df-opab 5174  df-mpt 5193  df-id 5556  df-po 5569  df-so 5570  df-xp 5667  df-rel 5668  df-cnv 5669  df-co 5670  df-dm 5671  df-rn 5672  df-res 5673  df-ima 5674  df-iota 6492  df-fun 6538  df-fn 6539  df-f 6540  df-f1 6541  df-fo 6542  df-f1o 6543  df-fv 6544  df-ov 7413  df-oprab 7414  df-mpo 7415  df-er 8690  df-en 8940  df-dom 8941  df-sdom 8942  df-pnf 11249  df-mnf 11250  df-xr 11251  df-ltxr 11252  df-le 11253  df-ico 13382

This theorem is used by:  rlimi2  15570  ello1mpt2  15578  dvfsumrlim  26199