Proof of Theorem xmulge0
Step | Hyp | Ref
| Expression |
1 | | xmulgt0 13017 |
. . . . . . . 8
⊢ (((𝐴 ∈ ℝ*
∧ 0 < 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 < 𝐵)) → 0 < (𝐴 ·e 𝐵)) |
2 | 1 | an4s 657 |
. . . . . . 7
⊢ (((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) ∧ (0 < 𝐴 ∧ 0 < 𝐵)) → 0 < (𝐴 ·e 𝐵)) |
3 | | 0xr 11022 |
. . . . . . . 8
⊢ 0 ∈
ℝ* |
4 | | xmulcl 13007 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (𝐴 ·e 𝐵) ∈
ℝ*) |
5 | 4 | adantr 481 |
. . . . . . . 8
⊢ (((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) ∧ (0 < 𝐴 ∧ 0 < 𝐵)) → (𝐴 ·e 𝐵) ∈
ℝ*) |
6 | | xrltle 12883 |
. . . . . . . 8
⊢ ((0
∈ ℝ* ∧ (𝐴 ·e 𝐵) ∈ ℝ*) → (0 <
(𝐴 ·e
𝐵) → 0 ≤ (𝐴 ·e 𝐵))) |
7 | 3, 5, 6 | sylancr 587 |
. . . . . . 7
⊢ (((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) ∧ (0 < 𝐴 ∧ 0 < 𝐵)) → (0 < (𝐴 ·e 𝐵) → 0 ≤ (𝐴 ·e 𝐵))) |
8 | 2, 7 | mpd 15 |
. . . . . 6
⊢ (((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) ∧ (0 < 𝐴 ∧ 0 < 𝐵)) → 0 ≤ (𝐴 ·e 𝐵)) |
9 | 8 | ex 413 |
. . . . 5
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → ((0 < 𝐴 ∧ 0 < 𝐵) → 0 ≤ (𝐴 ·e 𝐵))) |
10 | 9 | ad2ant2r 744 |
. . . 4
⊢ (((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) → ((0 < 𝐴 ∧ 0 < 𝐵) → 0 ≤ (𝐴 ·e 𝐵))) |
11 | 10 | impl 456 |
. . 3
⊢
(((((𝐴 ∈
ℝ* ∧ 0 ≤ 𝐴) ∧ (𝐵 ∈ ℝ* ∧ 0 ≤
𝐵)) ∧ 0 < 𝐴) ∧ 0 < 𝐵) → 0 ≤ (𝐴 ·e 𝐵)) |
12 | | 0le0 12074 |
. . . . 5
⊢ 0 ≤
0 |
13 | | oveq2 7283 |
. . . . . . 7
⊢ (0 =
𝐵 → (𝐴 ·e 0) = (𝐴 ·e 𝐵)) |
14 | 13 | eqcomd 2744 |
. . . . . 6
⊢ (0 =
𝐵 → (𝐴 ·e 𝐵) = (𝐴 ·e 0)) |
15 | | xmul01 13001 |
. . . . . . 7
⊢ (𝐴 ∈ ℝ*
→ (𝐴
·e 0) = 0) |
16 | 15 | ad2antrr 723 |
. . . . . 6
⊢ (((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) → (𝐴 ·e 0) =
0) |
17 | 14, 16 | sylan9eqr 2800 |
. . . . 5
⊢ ((((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) ∧ 0 = 𝐵) → (𝐴 ·e 𝐵) = 0) |
18 | 12, 17 | breqtrrid 5112 |
. . . 4
⊢ ((((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) ∧ 0 = 𝐵) → 0 ≤ (𝐴 ·e 𝐵)) |
19 | 18 | adantlr 712 |
. . 3
⊢
(((((𝐴 ∈
ℝ* ∧ 0 ≤ 𝐴) ∧ (𝐵 ∈ ℝ* ∧ 0 ≤
𝐵)) ∧ 0 < 𝐴) ∧ 0 = 𝐵) → 0 ≤ (𝐴 ·e 𝐵)) |
20 | | xrleloe 12878 |
. . . . . 6
⊢ ((0
∈ ℝ* ∧ 𝐵 ∈ ℝ*) → (0 ≤
𝐵 ↔ (0 < 𝐵 ∨ 0 = 𝐵))) |
21 | 3, 20 | mpan 687 |
. . . . 5
⊢ (𝐵 ∈ ℝ*
→ (0 ≤ 𝐵 ↔ (0
< 𝐵 ∨ 0 = 𝐵))) |
22 | 21 | biimpa 477 |
. . . 4
⊢ ((𝐵 ∈ ℝ*
∧ 0 ≤ 𝐵) → (0
< 𝐵 ∨ 0 = 𝐵)) |
23 | 22 | ad2antlr 724 |
. . 3
⊢ ((((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) ∧ 0 < 𝐴) → (0 < 𝐵 ∨ 0 = 𝐵)) |
24 | 11, 19, 23 | mpjaodan 956 |
. 2
⊢ ((((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) ∧ 0 < 𝐴) → 0 ≤ (𝐴 ·e 𝐵)) |
25 | | oveq1 7282 |
. . . . 5
⊢ (0 =
𝐴 → (0
·e 𝐵) =
(𝐴 ·e
𝐵)) |
26 | 25 | eqcomd 2744 |
. . . 4
⊢ (0 =
𝐴 → (𝐴 ·e 𝐵) = (0 ·e 𝐵)) |
27 | | xmul02 13002 |
. . . . 5
⊢ (𝐵 ∈ ℝ*
→ (0 ·e 𝐵) = 0) |
28 | 27 | ad2antrl 725 |
. . . 4
⊢ (((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) → (0 ·e 𝐵) = 0) |
29 | 26, 28 | sylan9eqr 2800 |
. . 3
⊢ ((((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) ∧ 0 = 𝐴) → (𝐴 ·e 𝐵) = 0) |
30 | 12, 29 | breqtrrid 5112 |
. 2
⊢ ((((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) ∧ 0 = 𝐴) → 0 ≤ (𝐴 ·e 𝐵)) |
31 | | xrleloe 12878 |
. . . . 5
⊢ ((0
∈ ℝ* ∧ 𝐴 ∈ ℝ*) → (0 ≤
𝐴 ↔ (0 < 𝐴 ∨ 0 = 𝐴))) |
32 | 3, 31 | mpan 687 |
. . . 4
⊢ (𝐴 ∈ ℝ*
→ (0 ≤ 𝐴 ↔ (0
< 𝐴 ∨ 0 = 𝐴))) |
33 | 32 | biimpa 477 |
. . 3
⊢ ((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) → (0
< 𝐴 ∨ 0 = 𝐴)) |
34 | 33 | adantr 481 |
. 2
⊢ (((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) → (0 < 𝐴 ∨ 0 = 𝐴)) |
35 | 24, 30, 34 | mpjaodan 956 |
1
⊢ (((𝐴 ∈ ℝ*
∧ 0 ≤ 𝐴) ∧
(𝐵 ∈
ℝ* ∧ 0 ≤ 𝐵)) → 0 ≤ (𝐴 ·e 𝐵)) |