| Step | Hyp | Ref
| Expression |
| 1 | | 0no 28195 |
. . . 4
⊢
0s ∈ No |
| 2 | | ltstrine 28108 |
. . . 4
⊢ ((𝐴 ∈ No ∧ 0s ∈ No) → (𝐴 ≠ 0s ↔ (𝐴 <s 0s ∨
0s <s 𝐴))) |
| 3 | 1, 2 | mpan2 704 |
. . 3
⊢ (𝐴 ∈ No → (𝐴 ≠ 0s ↔ (𝐴 <s 0s ∨
0s <s 𝐴))) |
| 4 | | ltnegs 28431 |
. . . . . . 7
⊢ ((𝐴 ∈ No ∧ 0s ∈ No) → (𝐴 <s 0s ↔ (
-s‘ 0s ) <s ( -s‘𝐴))) |
| 5 | 1, 4 | mpan2 704 |
. . . . . 6
⊢ (𝐴 ∈ No → (𝐴 <s 0s ↔ (
-s‘ 0s ) <s ( -s‘𝐴))) |
| 6 | | neg0s 28412 |
. . . . . . 7
⊢ (
-s‘ 0s ) = 0s |
| 7 | 6 | breq1i 5109 |
. . . . . 6
⊢ ((
-s‘ 0s ) <s ( -s‘𝐴) ↔ 0s <s (
-s‘𝐴)) |
| 8 | 5, 7 | bitrdi 290 |
. . . . 5
⊢ (𝐴 ∈ No → (𝐴 <s 0s ↔ 0s
<s ( -s‘𝐴))) |
| 9 | | negscl 28422 |
. . . . . . . 8
⊢ (𝐴 ∈ No → ( -s‘𝐴) ∈ No) |
| 10 | | precsex 28604 |
. . . . . . . 8
⊢ (((
-s‘𝐴)
∈ No ∧ 0s <s (
-s‘𝐴))
→ ∃𝑦 ∈
No (( -s‘𝐴) ·s 𝑦) = 1s ) |
| 11 | 9, 10 | sylan 592 |
. . . . . . 7
⊢ ((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) → ∃𝑦 ∈ No (( -s‘𝐴) ·s 𝑦) = 1s ) |
| 12 | | simprl 783 |
. . . . . . . . 9
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ (𝑦 ∈ No ∧
(( -s‘𝐴)
·s 𝑦) =
1s )) → 𝑦
∈ No) |
| 13 | 12 | negscld 28423 |
. . . . . . . 8
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ (𝑦 ∈ No ∧
(( -s‘𝐴)
·s 𝑦) =
1s )) → ( -s‘𝑦) ∈ No) |
| 14 | | simpll 779 |
. . . . . . . . . . . . 13
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ 𝑦 ∈ No)
→ 𝐴 ∈ No) |
| 15 | | simpr 490 |
. . . . . . . . . . . . 13
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ 𝑦 ∈ No)
→ 𝑦 ∈ No) |
| 16 | 14, 15 | mulnegs1d 28546 |
. . . . . . . . . . . 12
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ 𝑦 ∈ No)
→ (( -s‘𝐴) ·s 𝑦) = ( -s‘(𝐴 ·s 𝑦))) |
| 17 | 14, 15 | mulnegs2d 28547 |
. . . . . . . . . . . 12
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ 𝑦 ∈ No)
→ (𝐴
·s ( -s‘𝑦)) = ( -s‘(𝐴 ·s 𝑦))) |
| 18 | 16, 17 | eqtr4d 2798 |
. . . . . . . . . . 11
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ 𝑦 ∈ No)
→ (( -s‘𝐴) ·s 𝑦) = (𝐴 ·s (
-s‘𝑦))) |
| 19 | 18 | eqeq1d 2762 |
. . . . . . . . . 10
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ 𝑦 ∈ No)
→ ((( -s‘𝐴) ·s 𝑦) = 1s ↔ (𝐴 ·s (
-s‘𝑦)) =
1s )) |
| 20 | 19 | biimpd 232 |
. . . . . . . . 9
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ 𝑦 ∈ No)
→ ((( -s‘𝐴) ·s 𝑦) = 1s → (𝐴 ·s (
-s‘𝑦)) =
1s )) |
| 21 | 20 | impr 460 |
. . . . . . . 8
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ (𝑦 ∈ No ∧
(( -s‘𝐴)
·s 𝑦) =
1s )) → (𝐴
·s ( -s‘𝑦)) = 1s ) |
| 22 | | oveq2 7428 |
. . . . . . . . . 10
⊢ (𝑥 = ( -s‘𝑦) → (𝐴 ·s 𝑥) = (𝐴 ·s (
-s‘𝑦))) |
| 23 | 22 | eqeq1d 2762 |
. . . . . . . . 9
⊢ (𝑥 = ( -s‘𝑦) → ((𝐴 ·s 𝑥) = 1s ↔ (𝐴 ·s (
-s‘𝑦)) =
1s )) |
| 24 | 23 | rspcev 3576 |
. . . . . . . 8
⊢ (((
-s‘𝑦)
∈ No ∧ (𝐴 ·s (
-s‘𝑦)) =
1s ) → ∃𝑥 ∈ No
(𝐴 ·s
𝑥) = 1s
) |
| 25 | 13, 21, 24 | syl2anc 596 |
. . . . . . 7
⊢ (((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) ∧ (𝑦 ∈ No ∧
(( -s‘𝐴)
·s 𝑦) =
1s )) → ∃𝑥 ∈ No
(𝐴 ·s
𝑥) = 1s
) |
| 26 | 11, 25 | rexlimddv 3169 |
. . . . . 6
⊢ ((𝐴 ∈ No ∧ 0s <s ( -s‘𝐴)) → ∃𝑥 ∈ No (𝐴 ·s 𝑥) = 1s ) |
| 27 | 26 | ex 418 |
. . . . 5
⊢ (𝐴 ∈ No → ( 0s <s (
-s‘𝐴)
→ ∃𝑥 ∈
No (𝐴 ·s 𝑥) = 1s )) |
| 28 | 8, 27 | sylbid 243 |
. . . 4
⊢ (𝐴 ∈ No → (𝐴 <s 0s → ∃𝑥 ∈ No (𝐴 ·s 𝑥) = 1s )) |
| 29 | | precsex 28604 |
. . . . 5
⊢ ((𝐴 ∈ No ∧ 0s <s 𝐴) → ∃𝑥 ∈ No
(𝐴 ·s
𝑥) = 1s
) |
| 30 | 29 | ex 418 |
. . . 4
⊢ (𝐴 ∈ No → ( 0s <s 𝐴 → ∃𝑥 ∈ No
(𝐴 ·s
𝑥) = 1s
)) |
| 31 | 28, 30 | jaod 873 |
. . 3
⊢ (𝐴 ∈ No → ((𝐴 <s 0s ∨ 0s
<s 𝐴) →
∃𝑥 ∈ No (𝐴 ·s 𝑥) = 1s )) |
| 32 | 3, 31 | sylbid 243 |
. 2
⊢ (𝐴 ∈ No → (𝐴 ≠ 0s → ∃𝑥 ∈ No (𝐴 ·s 𝑥) = 1s )) |
| 33 | 32 | imp 412 |
1
⊢ ((𝐴 ∈ No ∧ 𝐴 ≠ 0s ) → ∃𝑥 ∈ No (𝐴 ·s 𝑥) = 1s ) |