Metamath Proof Explorer


Theorem isumrpcl

Description: The infinite sum of positive reals is positive. (Contributed by Paul Chapman, 9-Feb-2008) (Revised by Mario Carneiro, 24-Apr-2014)

Ref Expression
Hypotheses isumrpcl.1 ⊢ 𝑍 = ( ℤ≥ ‘ 𝑀 )
isumrpcl.2 ⊢ 𝑊 = ( ℤ≥ ‘ 𝑁 )
isumrpcl.3 ⊢ ( 𝜑 → 𝑁 ∈ 𝑍 )
isumrpcl.4 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) = 𝐴 )
isumrpcl.5 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → 𝐴 ∈ ℝ+ )
isumrpcl.6 ⊢ ( 𝜑 → seq 𝑀 ( + , 𝐹 ) ∈ dom ⇝ )
Assertion isumrpcl ( 𝜑 → Σ 𝑘 ∈ 𝑊 𝐴 ∈ ℝ+ )

Proof

Step Hyp Ref Expression
1 isumrpcl.1 ⊢ 𝑍 = ( ℤ≥ ‘ 𝑀 )
2 isumrpcl.2 ⊢ 𝑊 = ( ℤ≥ ‘ 𝑁 )
3 isumrpcl.3 ⊢ ( 𝜑 → 𝑁 ∈ 𝑍 )
4 isumrpcl.4 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) = 𝐴 )
5 isumrpcl.5 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → 𝐴 ∈ ℝ+ )
6 isumrpcl.6 ⊢ ( 𝜑 → seq 𝑀 ( + , 𝐹 ) ∈ dom ⇝ )
7 3 1 eleqtrdi ⊢ ( 𝜑 → 𝑁 ∈ ( ℤ≥ ‘ 𝑀 ) )
8 eluzelz ⊢ ( 𝑁 ∈ ( ℤ≥ ‘ 𝑀 ) → 𝑁 ∈ ℤ )
9 7 8 syl ⊢ ( 𝜑 → 𝑁 ∈ ℤ )
10 uzss ⊢ ( 𝑁 ∈ ( ℤ≥ ‘ 𝑀 ) → ( ℤ≥ ‘ 𝑁 ) ⊆ ( ℤ≥ ‘ 𝑀 ) )
11 7 10 syl ⊢ ( 𝜑 → ( ℤ≥ ‘ 𝑁 ) ⊆ ( ℤ≥ ‘ 𝑀 ) )
12 11 2 1 3sstr4g ⊢ ( 𝜑 → 𝑊 ⊆ 𝑍 )
13 12 sselda ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑊 ) → 𝑘 ∈ 𝑍 )
14 13 4 syldan ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑊 ) → ( 𝐹 ‘ 𝑘 ) = 𝐴 )
15 5 rpred ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → 𝐴 ∈ ℝ )
16 13 15 syldan ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑊 ) → 𝐴 ∈ ℝ )
17 4 5 eqeltrd ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) ∈ ℝ+ )
18 17 rpcnd ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑍 ) → ( 𝐹 ‘ 𝑘 ) ∈ ℂ )
19 1 3 18 iserex ⊢ ( 𝜑 → ( seq 𝑀 ( + , 𝐹 ) ∈ dom ⇝ ↔ seq 𝑁 ( + , 𝐹 ) ∈ dom ⇝ ) )
20 6 19 mpbid ⊢ ( 𝜑 → seq 𝑁 ( + , 𝐹 ) ∈ dom ⇝ )
21 2 9 14 16 20 isumrecl ⊢ ( 𝜑 → Σ 𝑘 ∈ 𝑊 𝐴 ∈ ℝ )
22 fveq2 ⊢ ( 𝑘 = 𝑁 → ( 𝐹 ‘ 𝑘 ) = ( 𝐹 ‘ 𝑁 ) )
23 22 eleq1d ⊢ ( 𝑘 = 𝑁 → ( ( 𝐹 ‘ 𝑘 ) ∈ ℝ+ ↔ ( 𝐹 ‘ 𝑁 ) ∈ ℝ+ ) )
24 17 ralrimiva ⊢ ( 𝜑 → ∀ 𝑘 ∈ 𝑍 ( 𝐹 ‘ 𝑘 ) ∈ ℝ+ )
25 23 24 3 rspcdva ⊢ ( 𝜑 → ( 𝐹 ‘ 𝑁 ) ∈ ℝ+ )
26 seq1 ⊢ ( 𝑁 ∈ ℤ → ( seq 𝑁 ( + , 𝐹 ) ‘ 𝑁 ) = ( 𝐹 ‘ 𝑁 ) )
27 9 26 syl ⊢ ( 𝜑 → ( seq 𝑁 ( + , 𝐹 ) ‘ 𝑁 ) = ( 𝐹 ‘ 𝑁 ) )
28 uzid ⊢ ( 𝑁 ∈ ℤ → 𝑁 ∈ ( ℤ≥ ‘ 𝑁 ) )
29 9 28 syl ⊢ ( 𝜑 → 𝑁 ∈ ( ℤ≥ ‘ 𝑁 ) )
30 29 2 eleqtrrdi ⊢ ( 𝜑 → 𝑁 ∈ 𝑊 )
31 16 recnd ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝑊 ) → 𝐴 ∈ ℂ )
32 2 9 14 31 20 isumclim2 ⊢ ( 𝜑 → seq 𝑁 ( + , 𝐹 ) ⇝ Σ 𝑘 ∈ 𝑊 𝐴 )
33 12 sseld ⊢ ( 𝜑 → ( 𝑚 ∈ 𝑊 → 𝑚 ∈ 𝑍 ) )
34 fveq2 ⊢ ( 𝑘 = 𝑚 → ( 𝐹 ‘ 𝑘 ) = ( 𝐹 ‘ 𝑚 ) )
35 34 eleq1d ⊢ ( 𝑘 = 𝑚 → ( ( 𝐹 ‘ 𝑘 ) ∈ ℝ+ ↔ ( 𝐹 ‘ 𝑚 ) ∈ ℝ+ ) )
36 35 rspcv ⊢ ( 𝑚 ∈ 𝑍 → ( ∀ 𝑘 ∈ 𝑍 ( 𝐹 ‘ 𝑘 ) ∈ ℝ+ → ( 𝐹 ‘ 𝑚 ) ∈ ℝ+ ) )
37 33 24 36 syl6ci ⊢ ( 𝜑 → ( 𝑚 ∈ 𝑊 → ( 𝐹 ‘ 𝑚 ) ∈ ℝ+ ) )
38 37 imp ⊢ ( ( 𝜑 ∧ 𝑚 ∈ 𝑊 ) → ( 𝐹 ‘ 𝑚 ) ∈ ℝ+ )
39 38 rpred ⊢ ( ( 𝜑 ∧ 𝑚 ∈ 𝑊 ) → ( 𝐹 ‘ 𝑚 ) ∈ ℝ )
40 38 rpge0d ⊢ ( ( 𝜑 ∧ 𝑚 ∈ 𝑊 ) → 0 ≤ ( 𝐹 ‘ 𝑚 ) )
41 2 30 32 39 40 climserle ⊢ ( 𝜑 → ( seq 𝑁 ( + , 𝐹 ) ‘ 𝑁 ) ≤ Σ 𝑘 ∈ 𝑊 𝐴 )
42 27 41 eqbrtrrd ⊢ ( 𝜑 → ( 𝐹 ‘ 𝑁 ) ≤ Σ 𝑘 ∈ 𝑊 𝐴 )
43 21 25 42 rpgecld ⊢ ( 𝜑 → Σ 𝑘 ∈ 𝑊 𝐴 ∈ ℝ+ )