Metamath Proof Explorer


Theorem radcnvlt1

Description: If X is within the open disk of radius R centered at zero, then the infinite series converges absolutely at X , and also converges when the series is multiplied by n . (Contributed by Mario Carneiro, 26-Feb-2015)

Ref Expression
Hypotheses pser.g 𝐺 = ( 𝑥 ∈ ℂ ↦ ( 𝑛 ∈ ℕ0 ↦ ( ( 𝐴𝑛 ) · ( 𝑥𝑛 ) ) ) )
radcnv.a ( 𝜑𝐴 : ℕ0 ⟶ ℂ )
radcnv.r 𝑅 = sup ( { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } , ℝ* , < )
radcnvlt.x ( 𝜑𝑋 ∈ ℂ )
radcnvlt.a ( 𝜑 → ( abs ‘ 𝑋 ) < 𝑅 )
radcnvlt1.h 𝐻 = ( 𝑚 ∈ ℕ0 ↦ ( 𝑚 · ( abs ‘ ( ( 𝐺𝑋 ) ‘ 𝑚 ) ) ) )
Assertion radcnvlt1 ( 𝜑 → ( seq 0 ( + , 𝐻 ) ∈ dom ⇝ ∧ seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ ) )

Proof

Step Hyp Ref Expression
1 pser.g 𝐺 = ( 𝑥 ∈ ℂ ↦ ( 𝑛 ∈ ℕ0 ↦ ( ( 𝐴𝑛 ) · ( 𝑥𝑛 ) ) ) )
2 radcnv.a ( 𝜑𝐴 : ℕ0 ⟶ ℂ )
3 radcnv.r 𝑅 = sup ( { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } , ℝ* , < )
4 radcnvlt.x ( 𝜑𝑋 ∈ ℂ )
5 radcnvlt.a ( 𝜑 → ( abs ‘ 𝑋 ) < 𝑅 )
6 radcnvlt1.h 𝐻 = ( 𝑚 ∈ ℕ0 ↦ ( 𝑚 · ( abs ‘ ( ( 𝐺𝑋 ) ‘ 𝑚 ) ) ) )
7 ressxr ℝ ⊆ ℝ*
8 4 abscld ( 𝜑 → ( abs ‘ 𝑋 ) ∈ ℝ )
9 7 8 sselid ( 𝜑 → ( abs ‘ 𝑋 ) ∈ ℝ* )
10 iccssxr ( 0 [,] +∞ ) ⊆ ℝ*
11 1 2 3 radcnvcl ( 𝜑𝑅 ∈ ( 0 [,] +∞ ) )
12 10 11 sselid ( 𝜑𝑅 ∈ ℝ* )
13 xrltnle ( ( ( abs ‘ 𝑋 ) ∈ ℝ*𝑅 ∈ ℝ* ) → ( ( abs ‘ 𝑋 ) < 𝑅 ↔ ¬ 𝑅 ≤ ( abs ‘ 𝑋 ) ) )
14 9 12 13 syl2anc ( 𝜑 → ( ( abs ‘ 𝑋 ) < 𝑅 ↔ ¬ 𝑅 ≤ ( abs ‘ 𝑋 ) ) )
15 5 14 mpbid ( 𝜑 → ¬ 𝑅 ≤ ( abs ‘ 𝑋 ) )
16 3 breq1i ( 𝑅 ≤ ( abs ‘ 𝑋 ) ↔ sup ( { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } , ℝ* , < ) ≤ ( abs ‘ 𝑋 ) )
17 ssrab2 { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } ⊆ ℝ
18 17 7 sstri { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } ⊆ ℝ*
19 supxrleub ( ( { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } ⊆ ℝ* ∧ ( abs ‘ 𝑋 ) ∈ ℝ* ) → ( sup ( { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } , ℝ* , < ) ≤ ( abs ‘ 𝑋 ) ↔ ∀ 𝑠 ∈ { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
20 18 9 19 sylancr ( 𝜑 → ( sup ( { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } , ℝ* , < ) ≤ ( abs ‘ 𝑋 ) ↔ ∀ 𝑠 ∈ { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
21 16 20 syl5bb ( 𝜑 → ( 𝑅 ≤ ( abs ‘ 𝑋 ) ↔ ∀ 𝑠 ∈ { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
22 fveq2 ( 𝑟 = 𝑠 → ( 𝐺𝑟 ) = ( 𝐺𝑠 ) )
23 22 seqeq3d ( 𝑟 = 𝑠 → seq 0 ( + , ( 𝐺𝑟 ) ) = seq 0 ( + , ( 𝐺𝑠 ) ) )
24 23 eleq1d ( 𝑟 = 𝑠 → ( seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ ↔ seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ) )
25 24 ralrab ( ∀ 𝑠 ∈ { 𝑟 ∈ ℝ ∣ seq 0 ( + , ( 𝐺𝑟 ) ) ∈ dom ⇝ } 𝑠 ≤ ( abs ‘ 𝑋 ) ↔ ∀ 𝑠 ∈ ℝ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ → 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
26 21 25 bitrdi ( 𝜑 → ( 𝑅 ≤ ( abs ‘ 𝑋 ) ↔ ∀ 𝑠 ∈ ℝ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ → 𝑠 ≤ ( abs ‘ 𝑋 ) ) ) )
27 15 26 mtbid ( 𝜑 → ¬ ∀ 𝑠 ∈ ℝ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ → 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
28 rexanali ( ∃ 𝑠 ∈ ℝ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) ) ↔ ¬ ∀ 𝑠 ∈ ℝ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ → 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
29 27 28 sylibr ( 𝜑 → ∃ 𝑠 ∈ ℝ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
30 ltnle ( ( ( abs ‘ 𝑋 ) ∈ ℝ ∧ 𝑠 ∈ ℝ ) → ( ( abs ‘ 𝑋 ) < 𝑠 ↔ ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
31 8 30 sylan ( ( 𝜑𝑠 ∈ ℝ ) → ( ( abs ‘ 𝑋 ) < 𝑠 ↔ ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
32 31 adantr ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ) → ( ( abs ‘ 𝑋 ) < 𝑠 ↔ ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) ) )
33 2 ad2antrr ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 𝐴 : ℕ0 ⟶ ℂ )
34 4 ad2antrr ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 𝑋 ∈ ℂ )
35 simplr ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 𝑠 ∈ ℝ )
36 35 recnd ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 𝑠 ∈ ℂ )
37 simprr ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → ( abs ‘ 𝑋 ) < 𝑠 )
38 0red ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 0 ∈ ℝ )
39 34 abscld ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → ( abs ‘ 𝑋 ) ∈ ℝ )
40 34 absge0d ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 0 ≤ ( abs ‘ 𝑋 ) )
41 38 39 35 40 37 lelttrd ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 0 < 𝑠 )
42 38 35 41 ltled ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → 0 ≤ 𝑠 )
43 35 42 absidd ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → ( abs ‘ 𝑠 ) = 𝑠 )
44 37 43 breqtrrd ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → ( abs ‘ 𝑋 ) < ( abs ‘ 𝑠 ) )
45 simprl ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ )
46 1 33 34 36 44 45 6 radcnvlem1 ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → seq 0 ( + , 𝐻 ) ∈ dom ⇝ )
47 1 33 34 36 44 45 radcnvlem2 ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ )
48 46 47 jca ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ( abs ‘ 𝑋 ) < 𝑠 ) ) → ( seq 0 ( + , 𝐻 ) ∈ dom ⇝ ∧ seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ ) )
49 48 expr ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ) → ( ( abs ‘ 𝑋 ) < 𝑠 → ( seq 0 ( + , 𝐻 ) ∈ dom ⇝ ∧ seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ ) ) )
50 32 49 sylbird ( ( ( 𝜑𝑠 ∈ ℝ ) ∧ seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ) → ( ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) → ( seq 0 ( + , 𝐻 ) ∈ dom ⇝ ∧ seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ ) ) )
51 50 expimpd ( ( 𝜑𝑠 ∈ ℝ ) → ( ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) ) → ( seq 0 ( + , 𝐻 ) ∈ dom ⇝ ∧ seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ ) ) )
52 51 rexlimdva ( 𝜑 → ( ∃ 𝑠 ∈ ℝ ( seq 0 ( + , ( 𝐺𝑠 ) ) ∈ dom ⇝ ∧ ¬ 𝑠 ≤ ( abs ‘ 𝑋 ) ) → ( seq 0 ( + , 𝐻 ) ∈ dom ⇝ ∧ seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ ) ) )
53 29 52 mpd ( 𝜑 → ( seq 0 ( + , 𝐻 ) ∈ dom ⇝ ∧ seq 0 ( + , ( abs ∘ ( 𝐺𝑋 ) ) ) ∈ dom ⇝ ) )