Metamath Proof Explorer


Theorem esumpr2

Description: Extended sum over a pair, with a relaxed condition compared to esumpr . (Contributed by Thierry Arnoux, 2-Jan-2017)

Ref Expression
Hypotheses esumpr.1 ( ( 𝜑𝑘 = 𝐴 ) → 𝐶 = 𝐷 )
esumpr.2 ( ( 𝜑𝑘 = 𝐵 ) → 𝐶 = 𝐸 )
esumpr.3 ( 𝜑𝐴𝑉 )
esumpr.4 ( 𝜑𝐵𝑊 )
esumpr.5 ( 𝜑𝐷 ∈ ( 0 [,] +∞ ) )
esumpr.6 ( 𝜑𝐸 ∈ ( 0 [,] +∞ ) )
esumpr2.1 ( 𝜑 → ( 𝐴 = 𝐵 → ( 𝐷 = 0 ∨ 𝐷 = +∞ ) ) )
Assertion esumpr2 ( 𝜑 → Σ* 𝑘 ∈ { 𝐴 , 𝐵 } 𝐶 = ( 𝐷 +𝑒 𝐸 ) )

Proof

Step Hyp Ref Expression
1 esumpr.1 ( ( 𝜑𝑘 = 𝐴 ) → 𝐶 = 𝐷 )
2 esumpr.2 ( ( 𝜑𝑘 = 𝐵 ) → 𝐶 = 𝐸 )
3 esumpr.3 ( 𝜑𝐴𝑉 )
4 esumpr.4 ( 𝜑𝐵𝑊 )
5 esumpr.5 ( 𝜑𝐷 ∈ ( 0 [,] +∞ ) )
6 esumpr.6 ( 𝜑𝐸 ∈ ( 0 [,] +∞ ) )
7 esumpr2.1 ( 𝜑 → ( 𝐴 = 𝐵 → ( 𝐷 = 0 ∨ 𝐷 = +∞ ) ) )
8 simpr ( ( 𝜑𝐴 = 𝐵 ) → 𝐴 = 𝐵 )
9 dfsn2 { 𝐴 } = { 𝐴 , 𝐴 }
10 preq2 ( 𝐴 = 𝐵 → { 𝐴 , 𝐴 } = { 𝐴 , 𝐵 } )
11 9 10 eqtr2id ( 𝐴 = 𝐵 → { 𝐴 , 𝐵 } = { 𝐴 } )
12 esumeq1 ( { 𝐴 , 𝐵 } = { 𝐴 } → Σ* 𝑘 ∈ { 𝐴 , 𝐵 } 𝐶 = Σ* 𝑘 ∈ { 𝐴 } 𝐶 )
13 8 11 12 3syl ( ( 𝜑𝐴 = 𝐵 ) → Σ* 𝑘 ∈ { 𝐴 , 𝐵 } 𝐶 = Σ* 𝑘 ∈ { 𝐴 } 𝐶 )
14 1 3 5 esumsn ( 𝜑 → Σ* 𝑘 ∈ { 𝐴 } 𝐶 = 𝐷 )
15 14 adantr ( ( 𝜑𝐴 = 𝐵 ) → Σ* 𝑘 ∈ { 𝐴 } 𝐶 = 𝐷 )
16 13 15 eqtrd ( ( 𝜑𝐴 = 𝐵 ) → Σ* 𝑘 ∈ { 𝐴 , 𝐵 } 𝐶 = 𝐷 )
17 oveq2 ( 𝐷 = 0 → ( 𝐷 +𝑒 𝐷 ) = ( 𝐷 +𝑒 0 ) )
18 0xr 0 ∈ ℝ*
19 eleq1 ( 𝐷 = 0 → ( 𝐷 ∈ ℝ* ↔ 0 ∈ ℝ* ) )
20 18 19 mpbiri ( 𝐷 = 0 → 𝐷 ∈ ℝ* )
21 xaddid1 ( 𝐷 ∈ ℝ* → ( 𝐷 +𝑒 0 ) = 𝐷 )
22 20 21 syl ( 𝐷 = 0 → ( 𝐷 +𝑒 0 ) = 𝐷 )
23 17 22 eqtrd ( 𝐷 = 0 → ( 𝐷 +𝑒 𝐷 ) = 𝐷 )
24 pnfxr +∞ ∈ ℝ*
25 eleq1 ( 𝐷 = +∞ → ( 𝐷 ∈ ℝ* ↔ +∞ ∈ ℝ* ) )
26 24 25 mpbiri ( 𝐷 = +∞ → 𝐷 ∈ ℝ* )
27 pnfnemnf +∞ ≠ -∞
28 neeq1 ( 𝐷 = +∞ → ( 𝐷 ≠ -∞ ↔ +∞ ≠ -∞ ) )
29 27 28 mpbiri ( 𝐷 = +∞ → 𝐷 ≠ -∞ )
30 xaddpnf1 ( ( 𝐷 ∈ ℝ*𝐷 ≠ -∞ ) → ( 𝐷 +𝑒 +∞ ) = +∞ )
31 26 29 30 syl2anc ( 𝐷 = +∞ → ( 𝐷 +𝑒 +∞ ) = +∞ )
32 oveq2 ( 𝐷 = +∞ → ( 𝐷 +𝑒 𝐷 ) = ( 𝐷 +𝑒 +∞ ) )
33 id ( 𝐷 = +∞ → 𝐷 = +∞ )
34 31 32 33 3eqtr4d ( 𝐷 = +∞ → ( 𝐷 +𝑒 𝐷 ) = 𝐷 )
35 23 34 jaoi ( ( 𝐷 = 0 ∨ 𝐷 = +∞ ) → ( 𝐷 +𝑒 𝐷 ) = 𝐷 )
36 7 35 syl6 ( 𝜑 → ( 𝐴 = 𝐵 → ( 𝐷 +𝑒 𝐷 ) = 𝐷 ) )
37 36 imp ( ( 𝜑𝐴 = 𝐵 ) → ( 𝐷 +𝑒 𝐷 ) = 𝐷 )
38 simpll ( ( ( 𝜑𝐴 = 𝐵 ) ∧ 𝑘 = 𝐵 ) → 𝜑 )
39 eqeq2 ( 𝐴 = 𝐵 → ( 𝑘 = 𝐴𝑘 = 𝐵 ) )
40 39 biimprd ( 𝐴 = 𝐵 → ( 𝑘 = 𝐵𝑘 = 𝐴 ) )
41 8 40 syl ( ( 𝜑𝐴 = 𝐵 ) → ( 𝑘 = 𝐵𝑘 = 𝐴 ) )
42 41 imp ( ( ( 𝜑𝐴 = 𝐵 ) ∧ 𝑘 = 𝐵 ) → 𝑘 = 𝐴 )
43 38 42 1 syl2anc ( ( ( 𝜑𝐴 = 𝐵 ) ∧ 𝑘 = 𝐵 ) → 𝐶 = 𝐷 )
44 4 adantr ( ( 𝜑𝐴 = 𝐵 ) → 𝐵𝑊 )
45 5 adantr ( ( 𝜑𝐴 = 𝐵 ) → 𝐷 ∈ ( 0 [,] +∞ ) )
46 43 44 45 esumsn ( ( 𝜑𝐴 = 𝐵 ) → Σ* 𝑘 ∈ { 𝐵 } 𝐶 = 𝐷 )
47 2 4 6 esumsn ( 𝜑 → Σ* 𝑘 ∈ { 𝐵 } 𝐶 = 𝐸 )
48 47 adantr ( ( 𝜑𝐴 = 𝐵 ) → Σ* 𝑘 ∈ { 𝐵 } 𝐶 = 𝐸 )
49 46 48 eqtr3d ( ( 𝜑𝐴 = 𝐵 ) → 𝐷 = 𝐸 )
50 49 oveq2d ( ( 𝜑𝐴 = 𝐵 ) → ( 𝐷 +𝑒 𝐷 ) = ( 𝐷 +𝑒 𝐸 ) )
51 16 37 50 3eqtr2d ( ( 𝜑𝐴 = 𝐵 ) → Σ* 𝑘 ∈ { 𝐴 , 𝐵 } 𝐶 = ( 𝐷 +𝑒 𝐸 ) )
52 1 adantlr ( ( ( 𝜑𝐴𝐵 ) ∧ 𝑘 = 𝐴 ) → 𝐶 = 𝐷 )
53 2 adantlr ( ( ( 𝜑𝐴𝐵 ) ∧ 𝑘 = 𝐵 ) → 𝐶 = 𝐸 )
54 3 adantr ( ( 𝜑𝐴𝐵 ) → 𝐴𝑉 )
55 4 adantr ( ( 𝜑𝐴𝐵 ) → 𝐵𝑊 )
56 5 adantr ( ( 𝜑𝐴𝐵 ) → 𝐷 ∈ ( 0 [,] +∞ ) )
57 6 adantr ( ( 𝜑𝐴𝐵 ) → 𝐸 ∈ ( 0 [,] +∞ ) )
58 simpr ( ( 𝜑𝐴𝐵 ) → 𝐴𝐵 )
59 52 53 54 55 56 57 58 esumpr ( ( 𝜑𝐴𝐵 ) → Σ* 𝑘 ∈ { 𝐴 , 𝐵 } 𝐶 = ( 𝐷 +𝑒 𝐸 ) )
60 51 59 pm2.61dane ( 𝜑 → Σ* 𝑘 ∈ { 𝐴 , 𝐵 } 𝐶 = ( 𝐷 +𝑒 𝐸 ) )