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Theorem fimaxre2 12016
Description: A nonempty finite set of real numbers has an upper bound. (Contributed by Jeff Madsen, 27-May-2011.) (Revised by Mario Carneiro, 13-Feb-2014.)
Assertion
Ref Expression
fimaxre2 ((𝐴 ⊆ ℝ ∧ 𝐴 ∈ Fin) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)
Distinct variable group:   𝑥,𝐴,𝑦

Proof of Theorem fimaxre2
Dummy variables 𝑠 𝑢 𝑣 𝑤 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 sseq1 3271 . . . 4 (𝑤 = ∅ → (𝑤 ⊆ ℝ ↔ ∅ ⊆ ℝ))
2 raleq 2749 . . . . 5 (𝑤 = ∅ → (∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∀𝑦 ∈ ∅ 𝑦 ≤ 𝑥))
32rexbidv 2551 . . . 4 (𝑤 = ∅ → (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∃𝑥 ∈ ℝ ∀𝑦 ∈ ∅ 𝑦 ≤ 𝑥))
41, 3imbi12d 234 . . 3 (𝑤 = ∅ → ((𝑤 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥) ↔ (∅ ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ ∅ 𝑦 ≤ 𝑥)))
5 sseq1 3271 . . . 4 (𝑤 = 𝑢 → (𝑤 ⊆ ℝ ↔ 𝑢 ⊆ ℝ))
6 raleq 2749 . . . . 5 (𝑤 = 𝑢 → (∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥))
76rexbidv 2551 . . . 4 (𝑤 = 𝑢 → (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥))
85, 7imbi12d 234 . . 3 (𝑤 = 𝑢 → ((𝑤 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥) ↔ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)))
9 sseq1 3271 . . . 4 (𝑤 = (𝑢 ∪ {𝑣}) → (𝑤 ⊆ ℝ ↔ (𝑢 ∪ {𝑣}) ⊆ ℝ))
10 raleq 2749 . . . . 5 (𝑤 = (𝑢 ∪ {𝑣}) → (∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥))
1110rexbidv 2551 . . . 4 (𝑤 = (𝑢 ∪ {𝑣}) → (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∃𝑥 ∈ ℝ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥))
129, 11imbi12d 234 . . 3 (𝑤 = (𝑢 ∪ {𝑣}) → ((𝑤 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥) ↔ ((𝑢 ∪ {𝑣}) ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥)))
13 sseq1 3271 . . . 4 (𝑤 = 𝐴 → (𝑤 ⊆ ℝ ↔ 𝐴 ⊆ ℝ))
14 raleq 2749 . . . . 5 (𝑤 = 𝐴 → (∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥))
1514rexbidv 2551 . . . 4 (𝑤 = 𝐴 → (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥 ↔ ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥))
1613, 15imbi12d 234 . . 3 (𝑤 = 𝐴 → ((𝑤 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑤 𝑦 ≤ 𝑥) ↔ (𝐴 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)))
17 0re 8332 . . . . 5 0 ∈ ℝ
18 ral0 3629 . . . . 5 ∀𝑦 ∈ ∅ 𝑦 ≤ 0
19 breq2 4135 . . . . . . 7 (𝑥 = 0 → (𝑦 ≤ 𝑥 ↔ 𝑦 ≤ 0))
2019ralbidv 2550 . . . . . 6 (𝑥 = 0 → (∀𝑦 ∈ ∅ 𝑦 ≤ 𝑥 ↔ ∀𝑦 ∈ ∅ 𝑦 ≤ 0))
2120rspcev 2929 . . . . 5 ((0 ∈ ℝ ∧ ∀𝑦 ∈ ∅ 𝑦 ≤ 0) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ ∅ 𝑦 ≤ 𝑥)
2217, 18, 21mp2an 430 . . . 4 ∃𝑥 ∈ ℝ ∀𝑦 ∈ ∅ 𝑦 ≤ 𝑥
2322a1i 9 . . 3 (∅ ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ ∅ 𝑦 ≤ 𝑥)
24 unss 3403 . . . . . . . . . 10 ((𝑢 ⊆ ℝ ∧ {𝑣} ⊆ ℝ) ↔ (𝑢 ∪ {𝑣}) ⊆ ℝ)
2524biimpri 133 . . . . . . . . 9 ((𝑢 ∪ {𝑣}) ⊆ ℝ → (𝑢 ⊆ ℝ ∧ {𝑣} ⊆ ℝ))
2625simpld 112 . . . . . . . 8 ((𝑢 ∪ {𝑣}) ⊆ ℝ → 𝑢 ⊆ ℝ)
2726adantl 277 . . . . . . 7 (((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) → 𝑢 ⊆ ℝ)
28 simplr 533 . . . . . . 7 (((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) → (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥))
2927, 28mpd 13 . . . . . 6 (((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)
30 breq2 4135 . . . . . . . 8 (𝑥 = 𝑠 → (𝑦 ≤ 𝑥 ↔ 𝑦 ≤ 𝑠))
3130ralbidv 2550 . . . . . . 7 (𝑥 = 𝑠 → (∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥 ↔ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠))
3231cbvrexv 2787 . . . . . 6 (∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥 ↔ ∃𝑠 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)
3329, 32sylib 122 . . . . 5 (((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) → ∃𝑠 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)
34 simprl 535 . . . . . . 7 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → 𝑠 ∈ ℝ)
3525simprd 114 . . . . . . . . 9 ((𝑢 ∪ {𝑣}) ⊆ ℝ → {𝑣} ⊆ ℝ)
36 vex 2824 . . . . . . . . . 10 𝑣 ∈ V
3736snss 3850 . . . . . . . . 9 (𝑣 ∈ ℝ ↔ {𝑣} ⊆ ℝ)
3835, 37sylibr 134 . . . . . . . 8 ((𝑢 ∪ {𝑣}) ⊆ ℝ → 𝑣 ∈ ℝ)
3938ad2antlr 493 . . . . . . 7 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → 𝑣 ∈ ℝ)
40 maxcl 11999 . . . . . . 7 ((𝑠 ∈ ℝ ∧ 𝑣 ∈ ℝ) → sup({𝑠, 𝑣}, ℝ, < ) ∈ ℝ)
4134, 39, 40syl2anc 415 . . . . . 6 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → sup({𝑠, 𝑣}, ℝ, < ) ∈ ℝ)
42 nfv 1581 . . . . . . . . . . 11 Ⅎ𝑦 𝑢 ∈ Fin
43 nfv 1581 . . . . . . . . . . . 12 Ⅎ𝑦 𝑢 ⊆ ℝ
44 nfcv 2392 . . . . . . . . . . . . 13 Ⅎ𝑦ℝ
45 nfra1 2581 . . . . . . . . . . . . 13 Ⅎ𝑦∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥
4644, 45nfrexw 2589 . . . . . . . . . . . 12 Ⅎ𝑦∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥
4743, 46nfim 1625 . . . . . . . . . . 11 Ⅎ𝑦(𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)
4842, 47nfan 1618 . . . . . . . . . 10 Ⅎ𝑦(𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥))
49 nfv 1581 . . . . . . . . . 10 Ⅎ𝑦(𝑢 ∪ {𝑣}) ⊆ ℝ
5048, 49nfan 1618 . . . . . . . . 9 Ⅎ𝑦((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ)
51 nfv 1581 . . . . . . . . . 10 Ⅎ𝑦 𝑠 ∈ ℝ
52 nfra1 2581 . . . . . . . . . 10 Ⅎ𝑦∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠
5351, 52nfan 1618 . . . . . . . . 9 Ⅎ𝑦(𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)
5450, 53nfan 1618 . . . . . . . 8 Ⅎ𝑦(((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠))
55 simprr 537 . . . . . . . . . . . 12 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)
56 maxle1 12000 . . . . . . . . . . . . 13 ((𝑠 ∈ ℝ ∧ 𝑣 ∈ ℝ) → 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < ))
5734, 39, 56syl2anc 415 . . . . . . . . . . . 12 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < ))
58 r19.27av 2686 . . . . . . . . . . . 12 ((∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠 ∧ 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < )) → ∀𝑦 ∈ 𝑢 (𝑦 ≤ 𝑠 ∧ 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < )))
5955, 57, 58syl2anc 415 . . . . . . . . . . 11 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → ∀𝑦 ∈ 𝑢 (𝑦 ≤ 𝑠 ∧ 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < )))
6059r19.21bi 2638 . . . . . . . . . 10 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → (𝑦 ≤ 𝑠 ∧ 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < )))
6127ad2antrr 492 . . . . . . . . . . . 12 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → 𝑢 ⊆ ℝ)
62 simpr 110 . . . . . . . . . . . 12 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → 𝑦 ∈ 𝑢)
6361, 62sseldd 3249 . . . . . . . . . . 11 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → 𝑦 ∈ ℝ)
6434adantr 276 . . . . . . . . . . 11 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → 𝑠 ∈ ℝ)
6541adantr 276 . . . . . . . . . . 11 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → sup({𝑠, 𝑣}, ℝ, < ) ∈ ℝ)
66 letr 8414 . . . . . . . . . . 11 ((𝑦 ∈ ℝ ∧ 𝑠 ∈ ℝ ∧ sup({𝑠, 𝑣}, ℝ, < ) ∈ ℝ) → ((𝑦 ≤ 𝑠 ∧ 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < )) → 𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < )))
6763, 64, 65, 66syl3anc 1278 . . . . . . . . . 10 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → ((𝑦 ≤ 𝑠 ∧ 𝑠 ≤ sup({𝑠, 𝑣}, ℝ, < )) → 𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < )))
6860, 67mpd 13 . . . . . . . . 9 (((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) ∧ 𝑦 ∈ 𝑢) → 𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ))
6968ex 115 . . . . . . . 8 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → (𝑦 ∈ 𝑢 → 𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < )))
7054, 69ralrimi 2621 . . . . . . 7 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → ∀𝑦 ∈ 𝑢 𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ))
71 maxle2 12001 . . . . . . . . 9 ((𝑠 ∈ ℝ ∧ 𝑣 ∈ ℝ) → 𝑣 ≤ sup({𝑠, 𝑣}, ℝ, < ))
7234, 39, 71syl2anc 415 . . . . . . . 8 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → 𝑣 ≤ sup({𝑠, 𝑣}, ℝ, < ))
73 breq1 4134 . . . . . . . . . 10 (𝑦 = 𝑣 → (𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ) ↔ 𝑣 ≤ sup({𝑠, 𝑣}, ℝ, < )))
7473ralsng 3749 . . . . . . . . 9 (𝑣 ∈ ℝ → (∀𝑦 ∈ {𝑣}𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ) ↔ 𝑣 ≤ sup({𝑠, 𝑣}, ℝ, < )))
7539, 74syl 14 . . . . . . . 8 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → (∀𝑦 ∈ {𝑣}𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ) ↔ 𝑣 ≤ sup({𝑠, 𝑣}, ℝ, < )))
7672, 75mpbird 167 . . . . . . 7 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → ∀𝑦 ∈ {𝑣}𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ))
77 ralun 3411 . . . . . . 7 ((∀𝑦 ∈ 𝑢 𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ) ∧ ∀𝑦 ∈ {𝑣}𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < )) → ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ))
7870, 76, 77syl2anc 415 . . . . . 6 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < ))
79 breq2 4135 . . . . . . . 8 (𝑥 = sup({𝑠, 𝑣}, ℝ, < ) → (𝑦 ≤ 𝑥 ↔ 𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < )))
8079ralbidv 2550 . . . . . . 7 (𝑥 = sup({𝑠, 𝑣}, ℝ, < ) → (∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥 ↔ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < )))
8180rspcev 2929 . . . . . 6 ((sup({𝑠, 𝑣}, ℝ, < ) ∈ ℝ ∧ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ sup({𝑠, 𝑣}, ℝ, < )) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥)
8241, 78, 81syl2anc 415 . . . . 5 ((((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) ∧ (𝑠 ∈ ℝ ∧ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑠)) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥)
8333, 82rexlimddv 2673 . . . 4 (((𝑢 ∈ Fin ∧ (𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥)) ∧ (𝑢 ∪ {𝑣}) ⊆ ℝ) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥)
8483exp31 364 . . 3 (𝑢 ∈ Fin → ((𝑢 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝑢 𝑦 ≤ 𝑥) → ((𝑢 ∪ {𝑣}) ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ (𝑢 ∪ {𝑣})𝑦 ≤ 𝑥)))
854, 8, 12, 16, 23, 84findcard2 7197 . 2 (𝐴 ∈ Fin → (𝐴 ⊆ ℝ → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥))
8685impcom 125 1 ((𝐴 ⊆ ℝ ∧ 𝐴 ∈ Fin) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)
Colors of variables:    wff set class
This proof depends on syntax axioms:   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1402   ∈ wcel 2209  ∀wral 2528  ∃wrex 2529   ∪ cun 3218   ⊆ wss 3220  ∅c0 3520  {csn 3709  {cpr 3710   class class class wbr 4131  Fincfn 7026  supcsup 7328  ℝcr 8184  0cc0 8185   < clt 8366   ≤ cle 8367
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-coll 4248  ax-sep 4251  ax-nul 4261  ax-pow 4313  ax-pr 4348  ax-un 4580  ax-setind 4686  ax-iinf 4737  ax-cnex 8276  ax-resscn 8277  ax-1cn 8278  ax-1re 8279  ax-icn 8280  ax-addcl 8281  ax-addrcl 8282  ax-mulcl 8283  ax-mulrcl 8284  ax-addcom 8285  ax-mulcom 8286  ax-addass 8287  ax-mulass 8288  ax-distr 8289  ax-i2m1 8290  ax-0lt1 8291  ax-1rid 8292  ax-0id 8293  ax-rnegex 8294  ax-precex 8295  ax-cnre 8296  ax-pre-ltirr 8297  ax-pre-ltwlin 8298  ax-pre-lttrn 8299  ax-pre-apti 8300  ax-pre-ltadd 8301  ax-pre-mulgt0 8302  ax-pre-mulext 8303  ax-arch 8304  ax-caucvg 8305
This proof depends on definitions:  df-bi 117  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-nel 2516  df-ral 2533  df-rex 2534  df-reu 2535  df-rmo 2536  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-if 3639  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-iun 4014  df-br 4132  df-opab 4194  df-mpt 4195  df-tr 4232  df-id 4440  df-po 4443  df-iso 4444  df-iord 4513  df-on 4515  df-ilim 4516  df-suc 4518  df-iom 4740  df-xp 4782  df-rel 4783  df-cnv 4784  df-co 4785  df-dm 4786  df-rn 4787  df-res 4788  df-ima 4789  df-iota 5340  df-fun 5382  df-fn 5383  df-f 5384  df-f1 5385  df-fo 5386  df-f1o 5387  df-fv 5388  df-riota 6041  df-ov 6091  df-oprab 6092  df-mpo 6093  df-1st 6378  df-2nd 6379  df-recs 6580  df-frec 6666  df-er 6811  df-en 7027  df-fin 7029  df-sup 7330  df-pnf 8368  df-mnf 8369  df-xr 8370  df-ltxr 8371  df-le 8372  df-sub 8506  df-neg 8507  df-reap 8911  df-ap 8918  df-div 9011  df-inn 9314  df-2 9372  df-3 9373  df-4 9374  df-n0 9575  df-z 9656  df-uz 9938  df-rp 10072  df-seqfrec 10906  df-exp 10997  df-cj 11629  df-re 11630  df-im 11631  df-rsqrt 11786  df-abs 11787
This theorem is used by:  fsum3cvg3  12188
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