Proof of Theorem xrge0addass
| Step | Hyp | Ref
| Expression |
| 1 | | iccssxr 13453 |
. . 3
⊢
(0[,]+∞) ⊆ ℝ* |
| 2 | | simp1 1136 |
. . 3
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐴
∈ (0[,]+∞)) |
| 3 | 1, 2 | sselid 3963 |
. 2
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐴
∈ ℝ*) |
| 4 | | 0xr 11291 |
. . . . . . 7
⊢ 0 ∈
ℝ* |
| 5 | 4 | a1i 11 |
. . . . . 6
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 0 ∈ ℝ*) |
| 6 | | pnfxr 11298 |
. . . . . . 7
⊢ +∞
∈ ℝ* |
| 7 | 6 | a1i 11 |
. . . . . 6
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → +∞ ∈ ℝ*) |
| 8 | | elicc4 13437 |
. . . . . 6
⊢ ((0
∈ ℝ* ∧ +∞ ∈ ℝ* ∧
𝐴 ∈
ℝ*) → (𝐴 ∈ (0[,]+∞) ↔ (0 ≤ 𝐴 ∧ 𝐴 ≤ +∞))) |
| 9 | 5, 7, 3, 8 | syl3anc 1372 |
. . . . 5
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → (𝐴
∈ (0[,]+∞) ↔ (0 ≤ 𝐴 ∧ 𝐴 ≤ +∞))) |
| 10 | 2, 9 | mpbid 232 |
. . . 4
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → (0 ≤ 𝐴 ∧ 𝐴 ≤ +∞)) |
| 11 | 10 | simpld 494 |
. . 3
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 0 ≤ 𝐴) |
| 12 | | ge0nemnf 13198 |
. . 3
⊢ ((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) →
𝐴 ≠
-∞) |
| 13 | 3, 11, 12 | syl2anc 584 |
. 2
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐴
≠ -∞) |
| 14 | | simp2 1137 |
. . 3
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐵
∈ (0[,]+∞)) |
| 15 | 1, 14 | sselid 3963 |
. 2
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐵
∈ ℝ*) |
| 16 | | elicc4 13437 |
. . . . . 6
⊢ ((0
∈ ℝ* ∧ +∞ ∈ ℝ* ∧
𝐵 ∈
ℝ*) → (𝐵 ∈ (0[,]+∞) ↔ (0 ≤ 𝐵 ∧ 𝐵 ≤ +∞))) |
| 17 | 5, 7, 15, 16 | syl3anc 1372 |
. . . . 5
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → (𝐵
∈ (0[,]+∞) ↔ (0 ≤ 𝐵 ∧ 𝐵 ≤ +∞))) |
| 18 | 14, 17 | mpbid 232 |
. . . 4
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → (0 ≤ 𝐵 ∧ 𝐵 ≤ +∞)) |
| 19 | 18 | simpld 494 |
. . 3
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 0 ≤ 𝐵) |
| 20 | | ge0nemnf 13198 |
. . 3
⊢ ((𝐵 ∈ ℝ*
∧ 0 ≤ 𝐵) →
𝐵 ≠
-∞) |
| 21 | 15, 19, 20 | syl2anc 584 |
. 2
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐵
≠ -∞) |
| 22 | | simp3 1138 |
. . 3
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐶
∈ (0[,]+∞)) |
| 23 | 1, 22 | sselid 3963 |
. 2
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐶
∈ ℝ*) |
| 24 | | elicc4 13437 |
. . . . . 6
⊢ ((0
∈ ℝ* ∧ +∞ ∈ ℝ* ∧
𝐶 ∈
ℝ*) → (𝐶 ∈ (0[,]+∞) ↔ (0 ≤ 𝐶 ∧ 𝐶 ≤ +∞))) |
| 25 | 5, 7, 23, 24 | syl3anc 1372 |
. . . . 5
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → (𝐶
∈ (0[,]+∞) ↔ (0 ≤ 𝐶 ∧ 𝐶 ≤ +∞))) |
| 26 | 22, 25 | mpbid 232 |
. . . 4
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → (0 ≤ 𝐶 ∧ 𝐶 ≤ +∞)) |
| 27 | 26 | simpld 494 |
. . 3
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 0 ≤ 𝐶) |
| 28 | | ge0nemnf 13198 |
. . 3
⊢ ((𝐶 ∈ ℝ*
∧ 0 ≤ 𝐶) →
𝐶 ≠
-∞) |
| 29 | 23, 27, 28 | syl2anc 584 |
. 2
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → 𝐶
≠ -∞) |
| 30 | | xaddass 13274 |
. 2
⊢ (((𝐴 ∈ ℝ*
∧ 𝐴 ≠ -∞)
∧ (𝐵 ∈
ℝ* ∧ 𝐵
≠ -∞) ∧ (𝐶
∈ ℝ* ∧ 𝐶 ≠ -∞)) → ((𝐴 +𝑒 𝐵) +𝑒 𝐶) = (𝐴 +𝑒 (𝐵 +𝑒 𝐶))) |
| 31 | 3, 13, 15, 21, 23, 29, 30 | syl222anc 1387 |
1
⊢ ((𝐴 ∈ (0[,]+∞) ∧
𝐵 ∈ (0[,]+∞)
∧ 𝐶 ∈
(0[,]+∞)) → ((𝐴
+𝑒 𝐵)
+𝑒 𝐶) =
(𝐴 +𝑒
(𝐵 +𝑒
𝐶))) |