Proof of Theorem telfsumo
| Step | Hyp | Ref
 | Expression | 
| 1 |   | sum0 11553 | 
. . . 4
⊢
Σ𝑗 ∈
∅ (𝐵 − 𝐶) = 0 | 
| 2 |   | telfsumo.3 | 
. . . . . . . 8
⊢ (𝑘 = 𝑀 → 𝐴 = 𝐷) | 
| 3 | 2 | eleq1d 2265 | 
. . . . . . 7
⊢ (𝑘 = 𝑀 → (𝐴 ∈ ℂ ↔ 𝐷 ∈ ℂ)) | 
| 4 |   | telfsumo.6 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑘 ∈ (𝑀...𝑁)) → 𝐴 ∈ ℂ) | 
| 5 | 4 | ralrimiva 2570 | 
. . . . . . 7
⊢ (𝜑 → ∀𝑘 ∈ (𝑀...𝑁)𝐴 ∈ ℂ) | 
| 6 |   | telfsumo.5 | 
. . . . . . . 8
⊢ (𝜑 → 𝑁 ∈ (ℤ≥‘𝑀)) | 
| 7 |   | eluzfz1 10106 | 
. . . . . . . 8
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑀 ∈ (𝑀...𝑁)) | 
| 8 | 6, 7 | syl 14 | 
. . . . . . 7
⊢ (𝜑 → 𝑀 ∈ (𝑀...𝑁)) | 
| 9 | 3, 5, 8 | rspcdva 2873 | 
. . . . . 6
⊢ (𝜑 → 𝐷 ∈ ℂ) | 
| 10 | 9 | adantr 276 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → 𝐷 ∈ ℂ) | 
| 11 | 10 | subidd 8325 | 
. . . 4
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → (𝐷 − 𝐷) = 0) | 
| 12 | 1, 11 | eqtr4id 2248 | 
. . 3
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → Σ𝑗 ∈ ∅ (𝐵 − 𝐶) = (𝐷 − 𝐷)) | 
| 13 |   | oveq2 5930 | 
. . . . . 6
⊢ (𝑁 = 𝑀 → (𝑀..^𝑁) = (𝑀..^𝑀)) | 
| 14 | 13 | adantl 277 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → (𝑀..^𝑁) = (𝑀..^𝑀)) | 
| 15 |   | fzo0 10244 | 
. . . . 5
⊢ (𝑀..^𝑀) = ∅ | 
| 16 | 14, 15 | eqtrdi 2245 | 
. . . 4
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → (𝑀..^𝑁) = ∅) | 
| 17 | 16 | sumeq1d 11531 | 
. . 3
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → Σ𝑗 ∈ (𝑀..^𝑁)(𝐵 − 𝐶) = Σ𝑗 ∈ ∅ (𝐵 − 𝐶)) | 
| 18 |   | eqeq1 2203 | 
. . . . . . . 8
⊢ (𝑘 = 𝑁 → (𝑘 = 𝑀 ↔ 𝑁 = 𝑀)) | 
| 19 |   | telfsumo.4 | 
. . . . . . . . 9
⊢ (𝑘 = 𝑁 → 𝐴 = 𝐸) | 
| 20 | 19 | eqeq1d 2205 | 
. . . . . . . 8
⊢ (𝑘 = 𝑁 → (𝐴 = 𝐷 ↔ 𝐸 = 𝐷)) | 
| 21 | 18, 20 | imbi12d 234 | 
. . . . . . 7
⊢ (𝑘 = 𝑁 → ((𝑘 = 𝑀 → 𝐴 = 𝐷) ↔ (𝑁 = 𝑀 → 𝐸 = 𝐷))) | 
| 22 | 21, 2 | vtoclg 2824 | 
. . . . . 6
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → (𝑁 = 𝑀 → 𝐸 = 𝐷)) | 
| 23 | 22 | imp 124 | 
. . . . 5
⊢ ((𝑁 ∈
(ℤ≥‘𝑀) ∧ 𝑁 = 𝑀) → 𝐸 = 𝐷) | 
| 24 | 6, 23 | sylan 283 | 
. . . 4
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → 𝐸 = 𝐷) | 
| 25 | 24 | oveq2d 5938 | 
. . 3
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → (𝐷 − 𝐸) = (𝐷 − 𝐷)) | 
| 26 | 12, 17, 25 | 3eqtr4d 2239 | 
. 2
⊢ ((𝜑 ∧ 𝑁 = 𝑀) → Σ𝑗 ∈ (𝑀..^𝑁)(𝐵 − 𝐶) = (𝐷 − 𝐸)) | 
| 27 |   | eluzel2 9606 | 
. . . . . . 7
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑀 ∈ ℤ) | 
| 28 | 6, 27 | syl 14 | 
. . . . . 6
⊢ (𝜑 → 𝑀 ∈ ℤ) | 
| 29 |   | eluzelz 9610 | 
. . . . . . 7
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑁 ∈ ℤ) | 
| 30 | 6, 29 | syl 14 | 
. . . . . 6
⊢ (𝜑 → 𝑁 ∈ ℤ) | 
| 31 |   | fzofig 10524 | 
. . . . . 6
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑀..^𝑁) ∈ Fin) | 
| 32 | 28, 30, 31 | syl2anc 411 | 
. . . . 5
⊢ (𝜑 → (𝑀..^𝑁) ∈ Fin) | 
| 33 |   | telfsumo.1 | 
. . . . . . 7
⊢ (𝑘 = 𝑗 → 𝐴 = 𝐵) | 
| 34 | 33 | eleq1d 2265 | 
. . . . . 6
⊢ (𝑘 = 𝑗 → (𝐴 ∈ ℂ ↔ 𝐵 ∈ ℂ)) | 
| 35 | 5 | adantr 276 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑗 ∈ (𝑀..^𝑁)) → ∀𝑘 ∈ (𝑀...𝑁)𝐴 ∈ ℂ) | 
| 36 |   | elfzofz 10238 | 
. . . . . . 7
⊢ (𝑗 ∈ (𝑀..^𝑁) → 𝑗 ∈ (𝑀...𝑁)) | 
| 37 | 36 | adantl 277 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑗 ∈ (𝑀..^𝑁)) → 𝑗 ∈ (𝑀...𝑁)) | 
| 38 | 34, 35, 37 | rspcdva 2873 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑗 ∈ (𝑀..^𝑁)) → 𝐵 ∈ ℂ) | 
| 39 |   | telfsumo.2 | 
. . . . . . 7
⊢ (𝑘 = (𝑗 + 1) → 𝐴 = 𝐶) | 
| 40 | 39 | eleq1d 2265 | 
. . . . . 6
⊢ (𝑘 = (𝑗 + 1) → (𝐴 ∈ ℂ ↔ 𝐶 ∈ ℂ)) | 
| 41 |   | fzofzp1 10303 | 
. . . . . . 7
⊢ (𝑗 ∈ (𝑀..^𝑁) → (𝑗 + 1) ∈ (𝑀...𝑁)) | 
| 42 | 41 | adantl 277 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑗 ∈ (𝑀..^𝑁)) → (𝑗 + 1) ∈ (𝑀...𝑁)) | 
| 43 | 40, 35, 42 | rspcdva 2873 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑗 ∈ (𝑀..^𝑁)) → 𝐶 ∈ ℂ) | 
| 44 | 32, 38, 43 | fsumsub 11617 | 
. . . 4
⊢ (𝜑 → Σ𝑗 ∈ (𝑀..^𝑁)(𝐵 − 𝐶) = (Σ𝑗 ∈ (𝑀..^𝑁)𝐵 − Σ𝑗 ∈ (𝑀..^𝑁)𝐶)) | 
| 45 | 44 | adantr 276 | 
. . 3
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑗 ∈ (𝑀..^𝑁)(𝐵 − 𝐶) = (Σ𝑗 ∈ (𝑀..^𝑁)𝐵 − Σ𝑗 ∈ (𝑀..^𝑁)𝐶)) | 
| 46 | 33 | cbvsumv 11526 | 
. . . . 5
⊢
Σ𝑘 ∈
(𝑀..^𝑁)𝐴 = Σ𝑗 ∈ (𝑀..^𝑁)𝐵 | 
| 47 |   | eluzp1m1 9625 | 
. . . . . . . 8
⊢ ((𝑀 ∈ ℤ ∧ 𝑁 ∈
(ℤ≥‘(𝑀 + 1))) → (𝑁 − 1) ∈
(ℤ≥‘𝑀)) | 
| 48 | 28, 47 | sylan 283 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → (𝑁 − 1) ∈
(ℤ≥‘𝑀)) | 
| 49 | 30 | adantr 276 | 
. . . . . . . . . . 11
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → 𝑁 ∈ ℤ) | 
| 50 |   | fzoval 10223 | 
. . . . . . . . . . 11
⊢ (𝑁 ∈ ℤ → (𝑀..^𝑁) = (𝑀...(𝑁 − 1))) | 
| 51 | 49, 50 | syl 14 | 
. . . . . . . . . 10
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → (𝑀..^𝑁) = (𝑀...(𝑁 − 1))) | 
| 52 |   | fzossfz 10241 | 
. . . . . . . . . 10
⊢ (𝑀..^𝑁) ⊆ (𝑀...𝑁) | 
| 53 | 51, 52 | eqsstrrdi 3236 | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → (𝑀...(𝑁 − 1)) ⊆ (𝑀...𝑁)) | 
| 54 | 53 | sselda 3183 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) ∧ 𝑘 ∈ (𝑀...(𝑁 − 1))) → 𝑘 ∈ (𝑀...𝑁)) | 
| 55 | 4 | adantlr 477 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) ∧ 𝑘 ∈ (𝑀...𝑁)) → 𝐴 ∈ ℂ) | 
| 56 | 54, 55 | syldan 282 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) ∧ 𝑘 ∈ (𝑀...(𝑁 − 1))) → 𝐴 ∈ ℂ) | 
| 57 | 48, 56, 2 | fsum1p 11583 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑘 ∈ (𝑀...(𝑁 − 1))𝐴 = (𝐷 + Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴)) | 
| 58 | 51 | sumeq1d 11531 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑘 ∈ (𝑀..^𝑁)𝐴 = Σ𝑘 ∈ (𝑀...(𝑁 − 1))𝐴) | 
| 59 |   | fzoval 10223 | 
. . . . . . . . 9
⊢ (𝑁 ∈ ℤ → ((𝑀 + 1)..^𝑁) = ((𝑀 + 1)...(𝑁 − 1))) | 
| 60 | 49, 59 | syl 14 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → ((𝑀 + 1)..^𝑁) = ((𝑀 + 1)...(𝑁 − 1))) | 
| 61 | 60 | sumeq1d 11531 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴 = Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴) | 
| 62 | 61 | oveq2d 5938 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → (𝐷 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴) = (𝐷 + Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴)) | 
| 63 | 57, 58, 62 | 3eqtr4d 2239 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑘 ∈ (𝑀..^𝑁)𝐴 = (𝐷 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) | 
| 64 | 46, 63 | eqtr3id 2243 | 
. . . 4
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑗 ∈ (𝑀..^𝑁)𝐵 = (𝐷 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) | 
| 65 |   | simpr 110 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) | 
| 66 |   | fzp1ss 10148 | 
. . . . . . . . . 10
⊢ (𝑀 ∈ ℤ → ((𝑀 + 1)...𝑁) ⊆ (𝑀...𝑁)) | 
| 67 | 28, 66 | syl 14 | 
. . . . . . . . 9
⊢ (𝜑 → ((𝑀 + 1)...𝑁) ⊆ (𝑀...𝑁)) | 
| 68 | 67 | sselda 3183 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑘 ∈ ((𝑀 + 1)...𝑁)) → 𝑘 ∈ (𝑀...𝑁)) | 
| 69 | 68, 4 | syldan 282 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑘 ∈ ((𝑀 + 1)...𝑁)) → 𝐴 ∈ ℂ) | 
| 70 | 69 | adantlr 477 | 
. . . . . 6
⊢ (((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) ∧ 𝑘 ∈ ((𝑀 + 1)...𝑁)) → 𝐴 ∈ ℂ) | 
| 71 | 65, 70, 19 | fsumm1 11581 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑘 ∈ ((𝑀 + 1)...𝑁)𝐴 = (Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴 + 𝐸)) | 
| 72 |   | 1zzd 9353 | 
. . . . . . . 8
⊢ (𝜑 → 1 ∈
ℤ) | 
| 73 | 28 | peano2zd 9451 | 
. . . . . . . 8
⊢ (𝜑 → (𝑀 + 1) ∈ ℤ) | 
| 74 | 72, 73, 30, 69, 39 | fsumshftm 11610 | 
. . . . . . 7
⊢ (𝜑 → Σ𝑘 ∈ ((𝑀 + 1)...𝑁)𝐴 = Σ𝑗 ∈ (((𝑀 + 1) − 1)...(𝑁 − 1))𝐶) | 
| 75 | 28 | zcnd 9449 | 
. . . . . . . . . . 11
⊢ (𝜑 → 𝑀 ∈ ℂ) | 
| 76 |   | ax-1cn 7972 | 
. . . . . . . . . . 11
⊢ 1 ∈
ℂ | 
| 77 |   | pncan 8232 | 
. . . . . . . . . . 11
⊢ ((𝑀 ∈ ℂ ∧ 1 ∈
ℂ) → ((𝑀 + 1)
− 1) = 𝑀) | 
| 78 | 75, 76, 77 | sylancl 413 | 
. . . . . . . . . 10
⊢ (𝜑 → ((𝑀 + 1) − 1) = 𝑀) | 
| 79 | 78 | oveq1d 5937 | 
. . . . . . . . 9
⊢ (𝜑 → (((𝑀 + 1) − 1)...(𝑁 − 1)) = (𝑀...(𝑁 − 1))) | 
| 80 | 30, 50 | syl 14 | 
. . . . . . . . 9
⊢ (𝜑 → (𝑀..^𝑁) = (𝑀...(𝑁 − 1))) | 
| 81 | 79, 80 | eqtr4d 2232 | 
. . . . . . . 8
⊢ (𝜑 → (((𝑀 + 1) − 1)...(𝑁 − 1)) = (𝑀..^𝑁)) | 
| 82 | 81 | sumeq1d 11531 | 
. . . . . . 7
⊢ (𝜑 → Σ𝑗 ∈ (((𝑀 + 1) − 1)...(𝑁 − 1))𝐶 = Σ𝑗 ∈ (𝑀..^𝑁)𝐶) | 
| 83 | 74, 82 | eqtrd 2229 | 
. . . . . 6
⊢ (𝜑 → Σ𝑘 ∈ ((𝑀 + 1)...𝑁)𝐴 = Σ𝑗 ∈ (𝑀..^𝑁)𝐶) | 
| 84 | 83 | adantr 276 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑘 ∈ ((𝑀 + 1)...𝑁)𝐴 = Σ𝑗 ∈ (𝑀..^𝑁)𝐶) | 
| 85 | 30, 59 | syl 14 | 
. . . . . . . . 9
⊢ (𝜑 → ((𝑀 + 1)..^𝑁) = ((𝑀 + 1)...(𝑁 − 1))) | 
| 86 | 85 | sumeq1d 11531 | 
. . . . . . . 8
⊢ (𝜑 → Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴 = Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴) | 
| 87 | 86 | oveq1d 5937 | 
. . . . . . 7
⊢ (𝜑 → (Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴 + 𝐸) = (Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴 + 𝐸)) | 
| 88 |   | fzofig 10524 | 
. . . . . . . . . 10
⊢ (((𝑀 + 1) ∈ ℤ ∧ 𝑁 ∈ ℤ) → ((𝑀 + 1)..^𝑁) ∈ Fin) | 
| 89 | 73, 30, 88 | syl2anc 411 | 
. . . . . . . . 9
⊢ (𝜑 → ((𝑀 + 1)..^𝑁) ∈ Fin) | 
| 90 |   | elfzofz 10238 | 
. . . . . . . . . 10
⊢ (𝑘 ∈ ((𝑀 + 1)..^𝑁) → 𝑘 ∈ ((𝑀 + 1)...𝑁)) | 
| 91 | 90, 69 | sylan2 286 | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑘 ∈ ((𝑀 + 1)..^𝑁)) → 𝐴 ∈ ℂ) | 
| 92 | 89, 91 | fsumcl 11565 | 
. . . . . . . 8
⊢ (𝜑 → Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴 ∈ ℂ) | 
| 93 | 19 | eleq1d 2265 | 
. . . . . . . . 9
⊢ (𝑘 = 𝑁 → (𝐴 ∈ ℂ ↔ 𝐸 ∈ ℂ)) | 
| 94 |   | eluzfz2 10107 | 
. . . . . . . . . 10
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑁 ∈ (𝑀...𝑁)) | 
| 95 | 6, 94 | syl 14 | 
. . . . . . . . 9
⊢ (𝜑 → 𝑁 ∈ (𝑀...𝑁)) | 
| 96 | 93, 5, 95 | rspcdva 2873 | 
. . . . . . . 8
⊢ (𝜑 → 𝐸 ∈ ℂ) | 
| 97 | 92, 96 | addcomd 8177 | 
. . . . . . 7
⊢ (𝜑 → (Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴 + 𝐸) = (𝐸 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) | 
| 98 | 87, 97 | eqtr3d 2231 | 
. . . . . 6
⊢ (𝜑 → (Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴 + 𝐸) = (𝐸 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) | 
| 99 | 98 | adantr 276 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → (Σ𝑘 ∈ ((𝑀 + 1)...(𝑁 − 1))𝐴 + 𝐸) = (𝐸 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) | 
| 100 | 71, 84, 99 | 3eqtr3d 2237 | 
. . . 4
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑗 ∈ (𝑀..^𝑁)𝐶 = (𝐸 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) | 
| 101 | 64, 100 | oveq12d 5940 | 
. . 3
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → (Σ𝑗 ∈ (𝑀..^𝑁)𝐵 − Σ𝑗 ∈ (𝑀..^𝑁)𝐶) = ((𝐷 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴) − (𝐸 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴))) | 
| 102 | 9, 96, 92 | pnpcan2d 8375 | 
. . . 4
⊢ (𝜑 → ((𝐷 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴) − (𝐸 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) = (𝐷 − 𝐸)) | 
| 103 | 102 | adantr 276 | 
. . 3
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → ((𝐷 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴) − (𝐸 + Σ𝑘 ∈ ((𝑀 + 1)..^𝑁)𝐴)) = (𝐷 − 𝐸)) | 
| 104 | 45, 101, 103 | 3eqtrd 2233 | 
. 2
⊢ ((𝜑 ∧ 𝑁 ∈ (ℤ≥‘(𝑀 + 1))) → Σ𝑗 ∈ (𝑀..^𝑁)(𝐵 − 𝐶) = (𝐷 − 𝐸)) | 
| 105 |   | uzp1 9635 | 
. . 3
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → (𝑁 = 𝑀 ∨ 𝑁 ∈ (ℤ≥‘(𝑀 + 1)))) | 
| 106 | 6, 105 | syl 14 | 
. 2
⊢ (𝜑 → (𝑁 = 𝑀 ∨ 𝑁 ∈ (ℤ≥‘(𝑀 + 1)))) | 
| 107 | 26, 104, 106 | mpjaodan 799 | 
1
⊢ (𝜑 → Σ𝑗 ∈ (𝑀..^𝑁)(𝐵 − 𝐶) = (𝐷 − 𝐸)) |