Proof of Theorem xltnegi
| Step | Hyp | Ref
| Expression |
| 1 | | elxr 8850 |
. . 3
⊢ (𝐴 ∈ ℝ*
↔ (𝐴 ∈ ℝ
∨ 𝐴 = +∞ ∨
𝐴 =
-∞)) |
| 2 | | elxr 8850 |
. . . . . 6
⊢ (𝐵 ∈ ℝ*
↔ (𝐵 ∈ ℝ
∨ 𝐵 = +∞ ∨
𝐵 =
-∞)) |
| 3 | | ltneg 7566 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 𝐵 ↔ -𝐵 < -𝐴)) |
| 4 | | rexneg 8897 |
. . . . . . . . . 10
⊢ (𝐵 ∈ ℝ →
-𝑒𝐵 =
-𝐵) |
| 5 | | rexneg 8897 |
. . . . . . . . . 10
⊢ (𝐴 ∈ ℝ →
-𝑒𝐴 =
-𝐴) |
| 6 | 4, 5 | breqan12rd 3801 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) →
(-𝑒𝐵
< -𝑒𝐴
↔ -𝐵 < -𝐴)) |
| 7 | 3, 6 | bitr4d 189 |
. . . . . . . 8
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 𝐵 ↔ -𝑒𝐵 < -𝑒𝐴)) |
| 8 | 7 | biimpd 142 |
. . . . . . 7
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 𝐵 → -𝑒𝐵 < -𝑒𝐴)) |
| 9 | | xnegeq 8894 |
. . . . . . . . . . 11
⊢ (𝐵 = +∞ →
-𝑒𝐵 =
-𝑒+∞) |
| 10 | | xnegpnf 8895 |
. . . . . . . . . . 11
⊢
-𝑒+∞ = -∞ |
| 11 | 9, 10 | syl6eq 2129 |
. . . . . . . . . 10
⊢ (𝐵 = +∞ →
-𝑒𝐵 =
-∞) |
| 12 | 11 | adantl 271 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) →
-𝑒𝐵 =
-∞) |
| 13 | | renegcl 7369 |
. . . . . . . . . . . 12
⊢ (𝐴 ∈ ℝ → -𝐴 ∈
ℝ) |
| 14 | 5, 13 | eqeltrd 2155 |
. . . . . . . . . . 11
⊢ (𝐴 ∈ ℝ →
-𝑒𝐴
∈ ℝ) |
| 15 | | mnflt 8858 |
. . . . . . . . . . 11
⊢
(-𝑒𝐴 ∈ ℝ → -∞ <
-𝑒𝐴) |
| 16 | 14, 15 | syl 14 |
. . . . . . . . . 10
⊢ (𝐴 ∈ ℝ → -∞
< -𝑒𝐴) |
| 17 | 16 | adantr 270 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → -∞
< -𝑒𝐴) |
| 18 | 12, 17 | eqbrtrd 3805 |
. . . . . . . 8
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) →
-𝑒𝐵 <
-𝑒𝐴) |
| 19 | 18 | a1d 22 |
. . . . . . 7
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = +∞) → (𝐴 < 𝐵 → -𝑒𝐵 < -𝑒𝐴)) |
| 20 | | simpr 108 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → 𝐵 = -∞) |
| 21 | 20 | breq2d 3797 |
. . . . . . . 8
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → (𝐴 < 𝐵 ↔ 𝐴 < -∞)) |
| 22 | | rexr 7164 |
. . . . . . . . . . 11
⊢ (𝐴 ∈ ℝ → 𝐴 ∈
ℝ*) |
| 23 | | nltmnf 8863 |
. . . . . . . . . . 11
⊢ (𝐴 ∈ ℝ*
→ ¬ 𝐴 <
-∞) |
| 24 | 22, 23 | syl 14 |
. . . . . . . . . 10
⊢ (𝐴 ∈ ℝ → ¬
𝐴 <
-∞) |
| 25 | 24 | adantr 270 |
. . . . . . . . 9
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → ¬ 𝐴 < -∞) |
| 26 | 25 | pm2.21d 581 |
. . . . . . . 8
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → (𝐴 < -∞ →
-𝑒𝐵 <
-𝑒𝐴)) |
| 27 | 21, 26 | sylbid 148 |
. . . . . . 7
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 = -∞) → (𝐴 < 𝐵 → -𝑒𝐵 < -𝑒𝐴)) |
| 28 | 8, 19, 27 | 3jaodan 1237 |
. . . . . 6
⊢ ((𝐴 ∈ ℝ ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞)) → (𝐴 < 𝐵 → -𝑒𝐵 < -𝑒𝐴)) |
| 29 | 2, 28 | sylan2b 281 |
. . . . 5
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ*)
→ (𝐴 < 𝐵 →
-𝑒𝐵 <
-𝑒𝐴)) |
| 30 | 29 | expimpd 355 |
. . . 4
⊢ (𝐴 ∈ ℝ → ((𝐵 ∈ ℝ*
∧ 𝐴 < 𝐵) →
-𝑒𝐵 <
-𝑒𝐴)) |
| 31 | | simpl 107 |
. . . . . . 7
⊢ ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*)
→ 𝐴 =
+∞) |
| 32 | 31 | breq1d 3795 |
. . . . . 6
⊢ ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*)
→ (𝐴 < 𝐵 ↔ +∞ < 𝐵)) |
| 33 | | pnfnlt 8862 |
. . . . . . . 8
⊢ (𝐵 ∈ ℝ*
→ ¬ +∞ < 𝐵) |
| 34 | 33 | adantl 271 |
. . . . . . 7
⊢ ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*)
→ ¬ +∞ < 𝐵) |
| 35 | 34 | pm2.21d 581 |
. . . . . 6
⊢ ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*)
→ (+∞ < 𝐵
→ -𝑒𝐵 < -𝑒𝐴)) |
| 36 | 32, 35 | sylbid 148 |
. . . . 5
⊢ ((𝐴 = +∞ ∧ 𝐵 ∈ ℝ*)
→ (𝐴 < 𝐵 →
-𝑒𝐵 <
-𝑒𝐴)) |
| 37 | 36 | expimpd 355 |
. . . 4
⊢ (𝐴 = +∞ → ((𝐵 ∈ ℝ*
∧ 𝐴 < 𝐵) →
-𝑒𝐵 <
-𝑒𝐴)) |
| 38 | | breq1 3788 |
. . . . . 6
⊢ (𝐴 = -∞ → (𝐴 < 𝐵 ↔ -∞ < 𝐵)) |
| 39 | 38 | anbi2d 451 |
. . . . 5
⊢ (𝐴 = -∞ → ((𝐵 ∈ ℝ*
∧ 𝐴 < 𝐵) ↔ (𝐵 ∈ ℝ* ∧ -∞
< 𝐵))) |
| 40 | | renegcl 7369 |
. . . . . . . . . . 11
⊢ (𝐵 ∈ ℝ → -𝐵 ∈
ℝ) |
| 41 | 4, 40 | eqeltrd 2155 |
. . . . . . . . . 10
⊢ (𝐵 ∈ ℝ →
-𝑒𝐵
∈ ℝ) |
| 42 | 41 | adantr 270 |
. . . . . . . . 9
⊢ ((𝐵 ∈ ℝ ∧ -∞
< 𝐵) →
-𝑒𝐵
∈ ℝ) |
| 43 | | ltpnf 8856 |
. . . . . . . . 9
⊢
(-𝑒𝐵 ∈ ℝ →
-𝑒𝐵 <
+∞) |
| 44 | 42, 43 | syl 14 |
. . . . . . . 8
⊢ ((𝐵 ∈ ℝ ∧ -∞
< 𝐵) →
-𝑒𝐵 <
+∞) |
| 45 | 11 | adantr 270 |
. . . . . . . . 9
⊢ ((𝐵 = +∞ ∧ -∞ <
𝐵) →
-𝑒𝐵 =
-∞) |
| 46 | | mnfltpnf 8860 |
. . . . . . . . 9
⊢ -∞
< +∞ |
| 47 | 45, 46 | syl6eqbr 3822 |
. . . . . . . 8
⊢ ((𝐵 = +∞ ∧ -∞ <
𝐵) →
-𝑒𝐵 <
+∞) |
| 48 | | breq2 3789 |
. . . . . . . . . 10
⊢ (𝐵 = -∞ → (-∞
< 𝐵 ↔ -∞ <
-∞)) |
| 49 | | mnfxr 8848 |
. . . . . . . . . . . 12
⊢ -∞
∈ ℝ* |
| 50 | | nltmnf 8863 |
. . . . . . . . . . . 12
⊢ (-∞
∈ ℝ* → ¬ -∞ <
-∞) |
| 51 | 49, 50 | ax-mp 7 |
. . . . . . . . . . 11
⊢ ¬
-∞ < -∞ |
| 52 | 51 | pm2.21i 607 |
. . . . . . . . . 10
⊢ (-∞
< -∞ → -𝑒𝐵 < +∞) |
| 53 | 48, 52 | syl6bi 161 |
. . . . . . . . 9
⊢ (𝐵 = -∞ → (-∞
< 𝐵 →
-𝑒𝐵 <
+∞)) |
| 54 | 53 | imp 122 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ -∞ <
𝐵) →
-𝑒𝐵 <
+∞) |
| 55 | 44, 47, 54 | 3jaoian 1236 |
. . . . . . 7
⊢ (((𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞) ∧ -∞ <
𝐵) →
-𝑒𝐵 <
+∞) |
| 56 | 2, 55 | sylanb 278 |
. . . . . 6
⊢ ((𝐵 ∈ ℝ*
∧ -∞ < 𝐵)
→ -𝑒𝐵 < +∞) |
| 57 | | xnegeq 8894 |
. . . . . . . 8
⊢ (𝐴 = -∞ →
-𝑒𝐴 =
-𝑒-∞) |
| 58 | | xnegmnf 8896 |
. . . . . . . 8
⊢
-𝑒-∞ = +∞ |
| 59 | 57, 58 | syl6eq 2129 |
. . . . . . 7
⊢ (𝐴 = -∞ →
-𝑒𝐴 =
+∞) |
| 60 | 59 | breq2d 3797 |
. . . . . 6
⊢ (𝐴 = -∞ →
(-𝑒𝐵
< -𝑒𝐴
↔ -𝑒𝐵 < +∞)) |
| 61 | 56, 60 | syl5ibr 154 |
. . . . 5
⊢ (𝐴 = -∞ → ((𝐵 ∈ ℝ*
∧ -∞ < 𝐵)
→ -𝑒𝐵 < -𝑒𝐴)) |
| 62 | 39, 61 | sylbid 148 |
. . . 4
⊢ (𝐴 = -∞ → ((𝐵 ∈ ℝ*
∧ 𝐴 < 𝐵) →
-𝑒𝐵 <
-𝑒𝐴)) |
| 63 | 30, 37, 62 | 3jaoi 1234 |
. . 3
⊢ ((𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞) → ((𝐵 ∈ ℝ*
∧ 𝐴 < 𝐵) →
-𝑒𝐵 <
-𝑒𝐴)) |
| 64 | 1, 63 | sylbi 119 |
. 2
⊢ (𝐴 ∈ ℝ*
→ ((𝐵 ∈
ℝ* ∧ 𝐴
< 𝐵) →
-𝑒𝐵 <
-𝑒𝐴)) |
| 65 | 64 | 3impib 1136 |
1
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ* ∧ 𝐴
< 𝐵) →
-𝑒𝐵 <
-𝑒𝐴) |