Metamath Proof Explorer


Theorem esummono

Description: Extended sum is monotonic. (Contributed by Thierry Arnoux, 19-Oct-2017)

Ref Expression
Hypotheses esummono.f 𝑘 𝜑
esummono.c ( 𝜑𝐶𝑉 )
esummono.b ( ( 𝜑𝑘𝐶 ) → 𝐵 ∈ ( 0 [,] +∞ ) )
esummono.a ( 𝜑𝐴𝐶 )
Assertion esummono ( 𝜑 → Σ* 𝑘𝐴 𝐵 ≤ Σ* 𝑘𝐶 𝐵 )

Proof

Step Hyp Ref Expression
1 esummono.f 𝑘 𝜑
2 esummono.c ( 𝜑𝐶𝑉 )
3 esummono.b ( ( 𝜑𝑘𝐶 ) → 𝐵 ∈ ( 0 [,] +∞ ) )
4 esummono.a ( 𝜑𝐴𝐶 )
5 2 difexd ( 𝜑 → ( 𝐶𝐴 ) ∈ V )
6 simpr ( ( 𝜑𝑘 ∈ ( 𝐶𝐴 ) ) → 𝑘 ∈ ( 𝐶𝐴 ) )
7 6 eldifad ( ( 𝜑𝑘 ∈ ( 𝐶𝐴 ) ) → 𝑘𝐶 )
8 7 3 syldan ( ( 𝜑𝑘 ∈ ( 𝐶𝐴 ) ) → 𝐵 ∈ ( 0 [,] +∞ ) )
9 8 ex ( 𝜑 → ( 𝑘 ∈ ( 𝐶𝐴 ) → 𝐵 ∈ ( 0 [,] +∞ ) ) )
10 1 9 ralrimi ( 𝜑 → ∀ 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) )
11 nfcv 𝑘 ( 𝐶𝐴 )
12 11 esumcl ( ( ( 𝐶𝐴 ) ∈ V ∧ ∀ 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) ) → Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) )
13 5 10 12 syl2anc ( 𝜑 → Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) )
14 elxrge0 ( Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) ↔ ( Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ℝ* ∧ 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) )
15 14 simprbi ( Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) → 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 )
16 13 15 syl ( 𝜑 → 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 )
17 iccssxr ( 0 [,] +∞ ) ⊆ ℝ*
18 2 4 ssexd ( 𝜑𝐴 ∈ V )
19 4 sselda ( ( 𝜑𝑘𝐴 ) → 𝑘𝐶 )
20 19 3 syldan ( ( 𝜑𝑘𝐴 ) → 𝐵 ∈ ( 0 [,] +∞ ) )
21 20 ex ( 𝜑 → ( 𝑘𝐴𝐵 ∈ ( 0 [,] +∞ ) ) )
22 1 21 ralrimi ( 𝜑 → ∀ 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
23 nfcv 𝑘 𝐴
24 23 esumcl ( ( 𝐴 ∈ V ∧ ∀ 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) ) → Σ* 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
25 18 22 24 syl2anc ( 𝜑 → Σ* 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
26 17 25 sselid ( 𝜑 → Σ* 𝑘𝐴 𝐵 ∈ ℝ* )
27 17 13 sselid ( 𝜑 → Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ℝ* )
28 xraddge02 ( ( Σ* 𝑘𝐴 𝐵 ∈ ℝ* ∧ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ℝ* ) → ( 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 → Σ* 𝑘𝐴 𝐵 ≤ ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) ) )
29 26 27 28 syl2anc ( 𝜑 → ( 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 → Σ* 𝑘𝐴 𝐵 ≤ ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) ) )
30 16 29 mpd ( 𝜑 → Σ* 𝑘𝐴 𝐵 ≤ ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) )
31 disjdif ( 𝐴 ∩ ( 𝐶𝐴 ) ) = ∅
32 31 a1i ( 𝜑 → ( 𝐴 ∩ ( 𝐶𝐴 ) ) = ∅ )
33 1 23 11 18 5 32 20 8 esumsplit ( 𝜑 → Σ* 𝑘 ∈ ( 𝐴 ∪ ( 𝐶𝐴 ) ) 𝐵 = ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) )
34 undif ( 𝐴𝐶 ↔ ( 𝐴 ∪ ( 𝐶𝐴 ) ) = 𝐶 )
35 4 34 sylib ( 𝜑 → ( 𝐴 ∪ ( 𝐶𝐴 ) ) = 𝐶 )
36 1 35 esumeq1d ( 𝜑 → Σ* 𝑘 ∈ ( 𝐴 ∪ ( 𝐶𝐴 ) ) 𝐵 = Σ* 𝑘𝐶 𝐵 )
37 33 36 eqtr3d ( 𝜑 → ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) = Σ* 𝑘𝐶 𝐵 )
38 30 37 breqtrd ( 𝜑 → Σ* 𝑘𝐴 𝐵 ≤ Σ* 𝑘𝐶 𝐵 )