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 difexg ( 𝐶𝑉 → ( 𝐶𝐴 ) ∈ V )
6 2 5 syl ( 𝜑 → ( 𝐶𝐴 ) ∈ V )
7 simpr ( ( 𝜑𝑘 ∈ ( 𝐶𝐴 ) ) → 𝑘 ∈ ( 𝐶𝐴 ) )
8 7 eldifad ( ( 𝜑𝑘 ∈ ( 𝐶𝐴 ) ) → 𝑘𝐶 )
9 8 3 syldan ( ( 𝜑𝑘 ∈ ( 𝐶𝐴 ) ) → 𝐵 ∈ ( 0 [,] +∞ ) )
10 9 ex ( 𝜑 → ( 𝑘 ∈ ( 𝐶𝐴 ) → 𝐵 ∈ ( 0 [,] +∞ ) ) )
11 1 10 ralrimi ( 𝜑 → ∀ 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) )
12 nfcv 𝑘 ( 𝐶𝐴 )
13 12 esumcl ( ( ( 𝐶𝐴 ) ∈ V ∧ ∀ 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) ) → Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) )
14 6 11 13 syl2anc ( 𝜑 → Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) )
15 elxrge0 ( Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) ↔ ( Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ℝ* ∧ 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) )
16 15 simprbi ( Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ( 0 [,] +∞ ) → 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 )
17 14 16 syl ( 𝜑 → 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 )
18 iccssxr ( 0 [,] +∞ ) ⊆ ℝ*
19 2 4 ssexd ( 𝜑𝐴 ∈ V )
20 4 sselda ( ( 𝜑𝑘𝐴 ) → 𝑘𝐶 )
21 20 3 syldan ( ( 𝜑𝑘𝐴 ) → 𝐵 ∈ ( 0 [,] +∞ ) )
22 21 ex ( 𝜑 → ( 𝑘𝐴𝐵 ∈ ( 0 [,] +∞ ) ) )
23 1 22 ralrimi ( 𝜑 → ∀ 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
24 nfcv 𝑘 𝐴
25 24 esumcl ( ( 𝐴 ∈ V ∧ ∀ 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) ) → Σ* 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
26 19 23 25 syl2anc ( 𝜑 → Σ* 𝑘𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
27 18 26 sseldi ( 𝜑 → Σ* 𝑘𝐴 𝐵 ∈ ℝ* )
28 18 14 sseldi ( 𝜑 → Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ∈ ℝ* )
29 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 ) ) )
30 27 28 29 syl2anc ( 𝜑 → ( 0 ≤ Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 → Σ* 𝑘𝐴 𝐵 ≤ ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) ) )
31 17 30 mpd ( 𝜑 → Σ* 𝑘𝐴 𝐵 ≤ ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) )
32 disjdif ( 𝐴 ∩ ( 𝐶𝐴 ) ) = ∅
33 32 a1i ( 𝜑 → ( 𝐴 ∩ ( 𝐶𝐴 ) ) = ∅ )
34 1 24 12 19 6 33 21 9 esumsplit ( 𝜑 → Σ* 𝑘 ∈ ( 𝐴 ∪ ( 𝐶𝐴 ) ) 𝐵 = ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) )
35 undif ( 𝐴𝐶 ↔ ( 𝐴 ∪ ( 𝐶𝐴 ) ) = 𝐶 )
36 4 35 sylib ( 𝜑 → ( 𝐴 ∪ ( 𝐶𝐴 ) ) = 𝐶 )
37 1 36 esumeq1d ( 𝜑 → Σ* 𝑘 ∈ ( 𝐴 ∪ ( 𝐶𝐴 ) ) 𝐵 = Σ* 𝑘𝐶 𝐵 )
38 34 37 eqtr3d ( 𝜑 → ( Σ* 𝑘𝐴 𝐵 +𝑒 Σ* 𝑘 ∈ ( 𝐶𝐴 ) 𝐵 ) = Σ* 𝑘𝐶 𝐵 )
39 31 38 breqtrd ( 𝜑 → Σ* 𝑘𝐴 𝐵 ≤ Σ* 𝑘𝐶 𝐵 )