| Step | Hyp | Ref
| Expression |
| 1 | | elq 12992 |
. . . . 5
⊢ (𝐴 ∈ ℚ ↔
∃𝑧 ∈ ℤ
∃𝑦 ∈ ℕ
𝐴 = (𝑧 / 𝑦)) |
| 2 | | rexcom 3290 |
. . . . 5
⊢
(∃𝑧 ∈
ℤ ∃𝑦 ∈
ℕ 𝐴 = (𝑧 / 𝑦) ↔ ∃𝑦 ∈ ℕ ∃𝑧 ∈ ℤ 𝐴 = (𝑧 / 𝑦)) |
| 3 | 1, 2 | bitri 275 |
. . . 4
⊢ (𝐴 ∈ ℚ ↔
∃𝑦 ∈ ℕ
∃𝑧 ∈ ℤ
𝐴 = (𝑧 / 𝑦)) |
| 4 | | breq2 5147 |
. . . . . . . . . . 11
⊢ (𝐴 = (𝑧 / 𝑦) → (0 < 𝐴 ↔ 0 < (𝑧 / 𝑦))) |
| 5 | | zre 12617 |
. . . . . . . . . . . . . 14
⊢ (𝑧 ∈ ℤ → 𝑧 ∈
ℝ) |
| 6 | 5 | adantl 481 |
. . . . . . . . . . . . 13
⊢ ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → 𝑧 ∈
ℝ) |
| 7 | | nnre 12273 |
. . . . . . . . . . . . . 14
⊢ (𝑦 ∈ ℕ → 𝑦 ∈
ℝ) |
| 8 | 7 | adantr 480 |
. . . . . . . . . . . . 13
⊢ ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → 𝑦 ∈
ℝ) |
| 9 | | nngt0 12297 |
. . . . . . . . . . . . . 14
⊢ (𝑦 ∈ ℕ → 0 <
𝑦) |
| 10 | 9 | adantr 480 |
. . . . . . . . . . . . 13
⊢ ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → 0 <
𝑦) |
| 11 | | gt0div 12134 |
. . . . . . . . . . . . 13
⊢ ((𝑧 ∈ ℝ ∧ 𝑦 ∈ ℝ ∧ 0 <
𝑦) → (0 < 𝑧 ↔ 0 < (𝑧 / 𝑦))) |
| 12 | 6, 8, 10, 11 | syl3anc 1373 |
. . . . . . . . . . . 12
⊢ ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → (0 <
𝑧 ↔ 0 < (𝑧 / 𝑦))) |
| 13 | 12 | bicomd 223 |
. . . . . . . . . . 11
⊢ ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → (0 <
(𝑧 / 𝑦) ↔ 0 < 𝑧)) |
| 14 | 4, 13 | sylan9bb 509 |
. . . . . . . . . 10
⊢ ((𝐴 = (𝑧 / 𝑦) ∧ (𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ)) → (0 < 𝐴 ↔ 0 < 𝑧)) |
| 15 | | oveq1 7438 |
. . . . . . . . . . . . 13
⊢ (𝑥 = 𝑧 → (𝑥 / 𝑦) = (𝑧 / 𝑦)) |
| 16 | 15 | eqeq2d 2748 |
. . . . . . . . . . . 12
⊢ (𝑥 = 𝑧 → (𝐴 = (𝑥 / 𝑦) ↔ 𝐴 = (𝑧 / 𝑦))) |
| 17 | | elnnz 12623 |
. . . . . . . . . . . . . . . 16
⊢ (𝑧 ∈ ℕ ↔ (𝑧 ∈ ℤ ∧ 0 <
𝑧)) |
| 18 | 17 | simplbi2 500 |
. . . . . . . . . . . . . . 15
⊢ (𝑧 ∈ ℤ → (0 <
𝑧 → 𝑧 ∈ ℕ)) |
| 19 | 18 | adantl 481 |
. . . . . . . . . . . . . 14
⊢ ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → (0 <
𝑧 → 𝑧 ∈ ℕ)) |
| 20 | 19 | adantl 481 |
. . . . . . . . . . . . 13
⊢ ((𝐴 = (𝑧 / 𝑦) ∧ (𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ)) → (0 < 𝑧 → 𝑧 ∈ ℕ)) |
| 21 | 20 | imp 406 |
. . . . . . . . . . . 12
⊢ (((𝐴 = (𝑧 / 𝑦) ∧ (𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ)) ∧ 0 < 𝑧) → 𝑧 ∈ ℕ) |
| 22 | | simpll 767 |
. . . . . . . . . . . 12
⊢ (((𝐴 = (𝑧 / 𝑦) ∧ (𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ)) ∧ 0 < 𝑧) → 𝐴 = (𝑧 / 𝑦)) |
| 23 | 16, 21, 22 | rspcedvdw 3625 |
. . . . . . . . . . 11
⊢ (((𝐴 = (𝑧 / 𝑦) ∧ (𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ)) ∧ 0 < 𝑧) → ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦)) |
| 24 | 23 | ex 412 |
. . . . . . . . . 10
⊢ ((𝐴 = (𝑧 / 𝑦) ∧ (𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ)) → (0 < 𝑧 → ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦))) |
| 25 | 14, 24 | sylbid 240 |
. . . . . . . . 9
⊢ ((𝐴 = (𝑧 / 𝑦) ∧ (𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ)) → (0 < 𝐴 → ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦))) |
| 26 | 25 | ex 412 |
. . . . . . . 8
⊢ (𝐴 = (𝑧 / 𝑦) → ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → (0 < 𝐴 → ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦)))) |
| 27 | 26 | com13 88 |
. . . . . . 7
⊢ (0 <
𝐴 → ((𝑦 ∈ ℕ ∧ 𝑧 ∈ ℤ) → (𝐴 = (𝑧 / 𝑦) → ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦)))) |
| 28 | 27 | impl 455 |
. . . . . 6
⊢ (((0 <
𝐴 ∧ 𝑦 ∈ ℕ) ∧ 𝑧 ∈ ℤ) → (𝐴 = (𝑧 / 𝑦) → ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦))) |
| 29 | 28 | rexlimdva 3155 |
. . . . 5
⊢ ((0 <
𝐴 ∧ 𝑦 ∈ ℕ) → (∃𝑧 ∈ ℤ 𝐴 = (𝑧 / 𝑦) → ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦))) |
| 30 | 29 | reximdva 3168 |
. . . 4
⊢ (0 <
𝐴 → (∃𝑦 ∈ ℕ ∃𝑧 ∈ ℤ 𝐴 = (𝑧 / 𝑦) → ∃𝑦 ∈ ℕ ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦))) |
| 31 | 3, 30 | biimtrid 242 |
. . 3
⊢ (0 <
𝐴 → (𝐴 ∈ ℚ → ∃𝑦 ∈ ℕ ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦))) |
| 32 | 31 | impcom 407 |
. 2
⊢ ((𝐴 ∈ ℚ ∧ 0 <
𝐴) → ∃𝑦 ∈ ℕ ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦)) |
| 33 | | rexcom 3290 |
. 2
⊢
(∃𝑥 ∈
ℕ ∃𝑦 ∈
ℕ 𝐴 = (𝑥 / 𝑦) ↔ ∃𝑦 ∈ ℕ ∃𝑥 ∈ ℕ 𝐴 = (𝑥 / 𝑦)) |
| 34 | 32, 33 | sylibr 234 |
1
⊢ ((𝐴 ∈ ℚ ∧ 0 <
𝐴) → ∃𝑥 ∈ ℕ ∃𝑦 ∈ ℕ 𝐴 = (𝑥 / 𝑦)) |