Proof of Theorem xnn0xaddcl
Step | Hyp | Ref
| Expression |
1 | | nn0addcl 12268 |
. . . . 5
⊢ ((𝐴 ∈ ℕ0
∧ 𝐵 ∈
ℕ0) → (𝐴 + 𝐵) ∈
ℕ0) |
2 | 1 | nn0xnn0d 12314 |
. . . 4
⊢ ((𝐴 ∈ ℕ0
∧ 𝐵 ∈
ℕ0) → (𝐴 + 𝐵) ∈
ℕ0*) |
3 | | nn0re 12242 |
. . . . 5
⊢ (𝐴 ∈ ℕ0
→ 𝐴 ∈
ℝ) |
4 | | nn0re 12242 |
. . . . 5
⊢ (𝐵 ∈ ℕ0
→ 𝐵 ∈
ℝ) |
5 | | rexadd 12966 |
. . . . . 6
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 +𝑒 𝐵) = (𝐴 + 𝐵)) |
6 | 5 | eleq1d 2823 |
. . . . 5
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → ((𝐴 +𝑒 𝐵) ∈
ℕ0* ↔ (𝐴 + 𝐵) ∈
ℕ0*)) |
7 | 3, 4, 6 | syl2an 596 |
. . . 4
⊢ ((𝐴 ∈ ℕ0
∧ 𝐵 ∈
ℕ0) → ((𝐴 +𝑒 𝐵) ∈ ℕ0*
↔ (𝐴 + 𝐵) ∈
ℕ0*)) |
8 | 2, 7 | mpbird 256 |
. . 3
⊢ ((𝐴 ∈ ℕ0
∧ 𝐵 ∈
ℕ0) → (𝐴 +𝑒 𝐵) ∈
ℕ0*) |
9 | 8 | a1d 25 |
. 2
⊢ ((𝐴 ∈ ℕ0
∧ 𝐵 ∈
ℕ0) → ((𝐴 ∈ ℕ0*
∧ 𝐵 ∈
ℕ0*) → (𝐴 +𝑒 𝐵) ∈
ℕ0*)) |
10 | | ianor 979 |
. . 3
⊢ (¬
(𝐴 ∈
ℕ0 ∧ 𝐵
∈ ℕ0) ↔ (¬ 𝐴 ∈ ℕ0 ∨ ¬ 𝐵 ∈
ℕ0)) |
11 | | xnn0nnn0pnf 12318 |
. . . . . . . . . 10
⊢ ((𝐴 ∈
ℕ0* ∧ ¬ 𝐴 ∈ ℕ0) → 𝐴 = +∞) |
12 | | oveq1 7282 |
. . . . . . . . . . . 12
⊢ (𝐴 = +∞ → (𝐴 +𝑒 𝐵) = (+∞
+𝑒 𝐵)) |
13 | | xnn0xrnemnf 12317 |
. . . . . . . . . . . . 13
⊢ (𝐵 ∈
ℕ0* → (𝐵 ∈ ℝ* ∧ 𝐵 ≠
-∞)) |
14 | | xaddpnf2 12961 |
. . . . . . . . . . . . 13
⊢ ((𝐵 ∈ ℝ*
∧ 𝐵 ≠ -∞)
→ (+∞ +𝑒 𝐵) = +∞) |
15 | 13, 14 | syl 17 |
. . . . . . . . . . . 12
⊢ (𝐵 ∈
ℕ0* → (+∞ +𝑒 𝐵) = +∞) |
16 | 12, 15 | sylan9eq 2798 |
. . . . . . . . . . 11
⊢ ((𝐴 = +∞ ∧ 𝐵 ∈
ℕ0*) → (𝐴 +𝑒 𝐵) = +∞) |
17 | 16 | ex 413 |
. . . . . . . . . 10
⊢ (𝐴 = +∞ → (𝐵 ∈
ℕ0* → (𝐴 +𝑒 𝐵) = +∞)) |
18 | 11, 17 | syl 17 |
. . . . . . . . 9
⊢ ((𝐴 ∈
ℕ0* ∧ ¬ 𝐴 ∈ ℕ0) → (𝐵 ∈
ℕ0* → (𝐴 +𝑒 𝐵) = +∞)) |
19 | 18 | expcom 414 |
. . . . . . . 8
⊢ (¬
𝐴 ∈
ℕ0 → (𝐴 ∈ ℕ0*
→ (𝐵 ∈
ℕ0* → (𝐴 +𝑒 𝐵) = +∞))) |
20 | 19 | impd 411 |
. . . . . . 7
⊢ (¬
𝐴 ∈
ℕ0 → ((𝐴 ∈ ℕ0*
∧ 𝐵 ∈
ℕ0*) → (𝐴 +𝑒 𝐵) = +∞)) |
21 | | xnn0nnn0pnf 12318 |
. . . . . . . . . 10
⊢ ((𝐵 ∈
ℕ0* ∧ ¬ 𝐵 ∈ ℕ0) → 𝐵 = +∞) |
22 | | oveq2 7283 |
. . . . . . . . . . . 12
⊢ (𝐵 = +∞ → (𝐴 +𝑒 𝐵) = (𝐴 +𝑒
+∞)) |
23 | | xnn0xrnemnf 12317 |
. . . . . . . . . . . . 13
⊢ (𝐴 ∈
ℕ0* → (𝐴 ∈ ℝ* ∧ 𝐴 ≠
-∞)) |
24 | | xaddpnf1 12960 |
. . . . . . . . . . . . 13
⊢ ((𝐴 ∈ ℝ*
∧ 𝐴 ≠ -∞)
→ (𝐴
+𝑒 +∞) = +∞) |
25 | 23, 24 | syl 17 |
. . . . . . . . . . . 12
⊢ (𝐴 ∈
ℕ0* → (𝐴 +𝑒 +∞) =
+∞) |
26 | 22, 25 | sylan9eq 2798 |
. . . . . . . . . . 11
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈
ℕ0*) → (𝐴 +𝑒 𝐵) = +∞) |
27 | 26 | ex 413 |
. . . . . . . . . 10
⊢ (𝐵 = +∞ → (𝐴 ∈
ℕ0* → (𝐴 +𝑒 𝐵) = +∞)) |
28 | 21, 27 | syl 17 |
. . . . . . . . 9
⊢ ((𝐵 ∈
ℕ0* ∧ ¬ 𝐵 ∈ ℕ0) → (𝐴 ∈
ℕ0* → (𝐴 +𝑒 𝐵) = +∞)) |
29 | 28 | expcom 414 |
. . . . . . . 8
⊢ (¬
𝐵 ∈
ℕ0 → (𝐵 ∈ ℕ0*
→ (𝐴 ∈
ℕ0* → (𝐴 +𝑒 𝐵) = +∞))) |
30 | 29 | impcomd 412 |
. . . . . . 7
⊢ (¬
𝐵 ∈
ℕ0 → ((𝐴 ∈ ℕ0*
∧ 𝐵 ∈
ℕ0*) → (𝐴 +𝑒 𝐵) = +∞)) |
31 | 20, 30 | jaoi 854 |
. . . . . 6
⊢ ((¬
𝐴 ∈
ℕ0 ∨ ¬ 𝐵 ∈ ℕ0) → ((𝐴 ∈
ℕ0* ∧ 𝐵 ∈ ℕ0*)
→ (𝐴
+𝑒 𝐵) =
+∞)) |
32 | 31 | imp 407 |
. . . . 5
⊢ (((¬
𝐴 ∈
ℕ0 ∨ ¬ 𝐵 ∈ ℕ0) ∧ (𝐴 ∈
ℕ0* ∧ 𝐵 ∈ ℕ0*))
→ (𝐴
+𝑒 𝐵) =
+∞) |
33 | | pnf0xnn0 12312 |
. . . . 5
⊢ +∞
∈ ℕ0* |
34 | 32, 33 | eqeltrdi 2847 |
. . . 4
⊢ (((¬
𝐴 ∈
ℕ0 ∨ ¬ 𝐵 ∈ ℕ0) ∧ (𝐴 ∈
ℕ0* ∧ 𝐵 ∈ ℕ0*))
→ (𝐴
+𝑒 𝐵)
∈ ℕ0*) |
35 | 34 | ex 413 |
. . 3
⊢ ((¬
𝐴 ∈
ℕ0 ∨ ¬ 𝐵 ∈ ℕ0) → ((𝐴 ∈
ℕ0* ∧ 𝐵 ∈ ℕ0*)
→ (𝐴
+𝑒 𝐵)
∈ ℕ0*)) |
36 | 10, 35 | sylbi 216 |
. 2
⊢ (¬
(𝐴 ∈
ℕ0 ∧ 𝐵
∈ ℕ0) → ((𝐴 ∈ ℕ0*
∧ 𝐵 ∈
ℕ0*) → (𝐴 +𝑒 𝐵) ∈
ℕ0*)) |
37 | 9, 36 | pm2.61i 182 |
1
⊢ ((𝐴 ∈
ℕ0* ∧ 𝐵 ∈ ℕ0*)
→ (𝐴
+𝑒 𝐵)
∈ ℕ0*) |