Proof of Theorem xrlttri3
| Step | Hyp | Ref
| Expression |
| 1 | | elxr 9851 |
. 2
⊢ (𝐴 ∈ ℝ*
↔ (𝐴 ∈ ℝ
∨ 𝐴 = +∞ ∨
𝐴 =
-∞)) |
| 2 | | elxr 9851 |
. 2
⊢ (𝐵 ∈ ℝ*
↔ (𝐵 ∈ ℝ
∨ 𝐵 = +∞ ∨
𝐵 =
-∞)) |
| 3 | | lttri3 8106 |
. . . . . 6
⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 4 | 3 | ancoms 268 |
. . . . 5
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 ∈ ℝ) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 5 | | renepnf 8074 |
. . . . . . . . . 10
⊢ (𝐵 ∈ ℝ → 𝐵 ≠ +∞) |
| 6 | 5 | adantr 276 |
. . . . . . . . 9
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → 𝐵 ≠ +∞) |
| 7 | | neeq2 2381 |
. . . . . . . . . 10
⊢ (𝐴 = +∞ → (𝐵 ≠ 𝐴 ↔ 𝐵 ≠ +∞)) |
| 8 | 7 | adantl 277 |
. . . . . . . . 9
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → (𝐵 ≠ 𝐴 ↔ 𝐵 ≠ +∞)) |
| 9 | 6, 8 | mpbird 167 |
. . . . . . . 8
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → 𝐵 ≠ 𝐴) |
| 10 | 9 | necomd 2453 |
. . . . . . 7
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → 𝐴 ≠ 𝐵) |
| 11 | 10 | neneqd 2388 |
. . . . . 6
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → ¬ 𝐴 = 𝐵) |
| 12 | | ltpnf 9855 |
. . . . . . . . 9
⊢ (𝐵 ∈ ℝ → 𝐵 < +∞) |
| 13 | 12 | adantr 276 |
. . . . . . . 8
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → 𝐵 < +∞) |
| 14 | | breq2 4037 |
. . . . . . . . 9
⊢ (𝐴 = +∞ → (𝐵 < 𝐴 ↔ 𝐵 < +∞)) |
| 15 | 14 | adantl 277 |
. . . . . . . 8
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → (𝐵 < 𝐴 ↔ 𝐵 < +∞)) |
| 16 | 13, 15 | mpbird 167 |
. . . . . . 7
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → 𝐵 < 𝐴) |
| 17 | | notnot 630 |
. . . . . . . . 9
⊢ ((𝐴 < 𝐵 ∨ 𝐵 < 𝐴) → ¬ ¬ (𝐴 < 𝐵 ∨ 𝐵 < 𝐴)) |
| 18 | 17 | olcs 737 |
. . . . . . . 8
⊢ (𝐵 < 𝐴 → ¬ ¬ (𝐴 < 𝐵 ∨ 𝐵 < 𝐴)) |
| 19 | | ioran 753 |
. . . . . . . 8
⊢ (¬
(𝐴 < 𝐵 ∨ 𝐵 < 𝐴) ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 20 | 18, 19 | sylnib 677 |
. . . . . . 7
⊢ (𝐵 < 𝐴 → ¬ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 21 | 16, 20 | syl 14 |
. . . . . 6
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → ¬ (¬
𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 22 | 11, 21 | 2falsed 703 |
. . . . 5
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = +∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 23 | | renemnf 8075 |
. . . . . . . . . 10
⊢ (𝐵 ∈ ℝ → 𝐵 ≠ -∞) |
| 24 | 23 | adantr 276 |
. . . . . . . . 9
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → 𝐵 ≠ -∞) |
| 25 | | neeq2 2381 |
. . . . . . . . . 10
⊢ (𝐴 = -∞ → (𝐵 ≠ 𝐴 ↔ 𝐵 ≠ -∞)) |
| 26 | 25 | adantl 277 |
. . . . . . . . 9
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → (𝐵 ≠ 𝐴 ↔ 𝐵 ≠ -∞)) |
| 27 | 24, 26 | mpbird 167 |
. . . . . . . 8
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → 𝐵 ≠ 𝐴) |
| 28 | 27 | necomd 2453 |
. . . . . . 7
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → 𝐴 ≠ 𝐵) |
| 29 | 28 | neneqd 2388 |
. . . . . 6
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → ¬ 𝐴 = 𝐵) |
| 30 | | mnflt 9858 |
. . . . . . . . 9
⊢ (𝐵 ∈ ℝ → -∞
< 𝐵) |
| 31 | 30 | adantr 276 |
. . . . . . . 8
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → -∞
< 𝐵) |
| 32 | | breq1 4036 |
. . . . . . . . 9
⊢ (𝐴 = -∞ → (𝐴 < 𝐵 ↔ -∞ < 𝐵)) |
| 33 | 32 | adantl 277 |
. . . . . . . 8
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → (𝐴 < 𝐵 ↔ -∞ < 𝐵)) |
| 34 | 31, 33 | mpbird 167 |
. . . . . . 7
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → 𝐴 < 𝐵) |
| 35 | | orc 713 |
. . . . . . 7
⊢ (𝐴 < 𝐵 → (𝐴 < 𝐵 ∨ 𝐵 < 𝐴)) |
| 36 | | oranim 782 |
. . . . . . 7
⊢ ((𝐴 < 𝐵 ∨ 𝐵 < 𝐴) → ¬ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 37 | 34, 35, 36 | 3syl 17 |
. . . . . 6
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → ¬ (¬
𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 38 | 29, 37 | 2falsed 703 |
. . . . 5
⊢ ((𝐵 ∈ ℝ ∧ 𝐴 = -∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 39 | 4, 22, 38 | 3jaodan 1317 |
. . . 4
⊢ ((𝐵 ∈ ℝ ∧ (𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞)) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 40 | 39 | ancoms 268 |
. . 3
⊢ (((𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞) ∧ 𝐵 ∈ ℝ) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 41 | | renepnf 8074 |
. . . . . . . . 9
⊢ (𝐴 ∈ ℝ → 𝐴 ≠ +∞) |
| 42 | 41 | adantl 277 |
. . . . . . . 8
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → 𝐴 ≠ +∞) |
| 43 | | neeq2 2381 |
. . . . . . . . 9
⊢ (𝐵 = +∞ → (𝐴 ≠ 𝐵 ↔ 𝐴 ≠ +∞)) |
| 44 | 43 | adantr 276 |
. . . . . . . 8
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → (𝐴 ≠ 𝐵 ↔ 𝐴 ≠ +∞)) |
| 45 | 42, 44 | mpbird 167 |
. . . . . . 7
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → 𝐴 ≠ 𝐵) |
| 46 | 45 | neneqd 2388 |
. . . . . 6
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → ¬
𝐴 = 𝐵) |
| 47 | | ltpnf 9855 |
. . . . . . . . 9
⊢ (𝐴 ∈ ℝ → 𝐴 < +∞) |
| 48 | 47 | adantl 277 |
. . . . . . . 8
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → 𝐴 < +∞) |
| 49 | | breq2 4037 |
. . . . . . . . 9
⊢ (𝐵 = +∞ → (𝐴 < 𝐵 ↔ 𝐴 < +∞)) |
| 50 | 49 | adantr 276 |
. . . . . . . 8
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → (𝐴 < 𝐵 ↔ 𝐴 < +∞)) |
| 51 | 48, 50 | mpbird 167 |
. . . . . . 7
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → 𝐴 < 𝐵) |
| 52 | 51, 35, 36 | 3syl 17 |
. . . . . 6
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → ¬
(¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 53 | 46, 52 | 2falsed 703 |
. . . . 5
⊢ ((𝐵 = +∞ ∧ 𝐴 ∈ ℝ) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 54 | | eqtr3 2216 |
. . . . . . 7
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → 𝐵 = 𝐴) |
| 55 | 54 | eqcomd 2202 |
. . . . . 6
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → 𝐴 = 𝐵) |
| 56 | | pnfxr 8079 |
. . . . . . . . 9
⊢ +∞
∈ ℝ* |
| 57 | | xrltnr 9854 |
. . . . . . . . 9
⊢ (+∞
∈ ℝ* → ¬ +∞ <
+∞) |
| 58 | 56, 57 | ax-mp 5 |
. . . . . . . 8
⊢ ¬
+∞ < +∞ |
| 59 | | breq12 4038 |
. . . . . . . . 9
⊢ ((𝐴 = +∞ ∧ 𝐵 = +∞) → (𝐴 < 𝐵 ↔ +∞ <
+∞)) |
| 60 | 59 | ancoms 268 |
. . . . . . . 8
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → (𝐴 < 𝐵 ↔ +∞ <
+∞)) |
| 61 | 58, 60 | mtbiri 676 |
. . . . . . 7
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → ¬ 𝐴 < 𝐵) |
| 62 | | breq12 4038 |
. . . . . . . 8
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → (𝐵 < 𝐴 ↔ +∞ <
+∞)) |
| 63 | 58, 62 | mtbiri 676 |
. . . . . . 7
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → ¬ 𝐵 < 𝐴) |
| 64 | 61, 63 | jca 306 |
. . . . . 6
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 65 | 55, 64 | 2thd 175 |
. . . . 5
⊢ ((𝐵 = +∞ ∧ 𝐴 = +∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 66 | | mnfnepnf 8082 |
. . . . . . . . 9
⊢ -∞
≠ +∞ |
| 67 | | eqeq12 2209 |
. . . . . . . . . 10
⊢ ((𝐴 = -∞ ∧ 𝐵 = +∞) → (𝐴 = 𝐵 ↔ -∞ =
+∞)) |
| 68 | 67 | necon3bid 2408 |
. . . . . . . . 9
⊢ ((𝐴 = -∞ ∧ 𝐵 = +∞) → (𝐴 ≠ 𝐵 ↔ -∞ ≠
+∞)) |
| 69 | 66, 68 | mpbiri 168 |
. . . . . . . 8
⊢ ((𝐴 = -∞ ∧ 𝐵 = +∞) → 𝐴 ≠ 𝐵) |
| 70 | 69 | ancoms 268 |
. . . . . . 7
⊢ ((𝐵 = +∞ ∧ 𝐴 = -∞) → 𝐴 ≠ 𝐵) |
| 71 | 70 | neneqd 2388 |
. . . . . 6
⊢ ((𝐵 = +∞ ∧ 𝐴 = -∞) → ¬ 𝐴 = 𝐵) |
| 72 | | mnfltpnf 9860 |
. . . . . . . . 9
⊢ -∞
< +∞ |
| 73 | | breq12 4038 |
. . . . . . . . 9
⊢ ((𝐴 = -∞ ∧ 𝐵 = +∞) → (𝐴 < 𝐵 ↔ -∞ <
+∞)) |
| 74 | 72, 73 | mpbiri 168 |
. . . . . . . 8
⊢ ((𝐴 = -∞ ∧ 𝐵 = +∞) → 𝐴 < 𝐵) |
| 75 | 74 | ancoms 268 |
. . . . . . 7
⊢ ((𝐵 = +∞ ∧ 𝐴 = -∞) → 𝐴 < 𝐵) |
| 76 | 75, 35, 36 | 3syl 17 |
. . . . . 6
⊢ ((𝐵 = +∞ ∧ 𝐴 = -∞) → ¬ (¬
𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 77 | 71, 76 | 2falsed 703 |
. . . . 5
⊢ ((𝐵 = +∞ ∧ 𝐴 = -∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 78 | 53, 65, 77 | 3jaodan 1317 |
. . . 4
⊢ ((𝐵 = +∞ ∧ (𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞)) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 79 | 78 | ancoms 268 |
. . 3
⊢ (((𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞) ∧ 𝐵 = +∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 80 | | renemnf 8075 |
. . . . . . . . 9
⊢ (𝐴 ∈ ℝ → 𝐴 ≠ -∞) |
| 81 | 80 | adantl 277 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → 𝐴 ≠ -∞) |
| 82 | | neeq2 2381 |
. . . . . . . . 9
⊢ (𝐵 = -∞ → (𝐴 ≠ 𝐵 ↔ 𝐴 ≠ -∞)) |
| 83 | 82 | adantr 276 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → (𝐴 ≠ 𝐵 ↔ 𝐴 ≠ -∞)) |
| 84 | 81, 83 | mpbird 167 |
. . . . . . 7
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → 𝐴 ≠ 𝐵) |
| 85 | 84 | neneqd 2388 |
. . . . . 6
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → ¬
𝐴 = 𝐵) |
| 86 | | mnflt 9858 |
. . . . . . . . 9
⊢ (𝐴 ∈ ℝ → -∞
< 𝐴) |
| 87 | 86 | adantl 277 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → -∞
< 𝐴) |
| 88 | | breq1 4036 |
. . . . . . . . 9
⊢ (𝐵 = -∞ → (𝐵 < 𝐴 ↔ -∞ < 𝐴)) |
| 89 | 88 | adantr 276 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → (𝐵 < 𝐴 ↔ -∞ < 𝐴)) |
| 90 | 87, 89 | mpbird 167 |
. . . . . . 7
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → 𝐵 < 𝐴) |
| 91 | 90, 20 | syl 14 |
. . . . . 6
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → ¬
(¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 92 | 85, 91 | 2falsed 703 |
. . . . 5
⊢ ((𝐵 = -∞ ∧ 𝐴 ∈ ℝ) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 93 | 66 | neii 2369 |
. . . . . . . . . 10
⊢ ¬
-∞ = +∞ |
| 94 | | eqeq12 2209 |
. . . . . . . . . 10
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → (𝐵 = 𝐴 ↔ -∞ =
+∞)) |
| 95 | 93, 94 | mtbiri 676 |
. . . . . . . . 9
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → ¬ 𝐵 = 𝐴) |
| 96 | 95 | neneqad 2446 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → 𝐵 ≠ 𝐴) |
| 97 | 96 | necomd 2453 |
. . . . . . 7
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → 𝐴 ≠ 𝐵) |
| 98 | 97 | neneqd 2388 |
. . . . . 6
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → ¬ 𝐴 = 𝐵) |
| 99 | | breq12 4038 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → (𝐵 < 𝐴 ↔ -∞ <
+∞)) |
| 100 | 72, 99 | mpbiri 168 |
. . . . . . 7
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → 𝐵 < 𝐴) |
| 101 | 100, 20 | syl 14 |
. . . . . 6
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → ¬ (¬
𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 102 | 98, 101 | 2falsed 703 |
. . . . 5
⊢ ((𝐵 = -∞ ∧ 𝐴 = +∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 103 | | eqtr3 2216 |
. . . . . . 7
⊢ ((𝐴 = -∞ ∧ 𝐵 = -∞) → 𝐴 = 𝐵) |
| 104 | 103 | ancoms 268 |
. . . . . 6
⊢ ((𝐵 = -∞ ∧ 𝐴 = -∞) → 𝐴 = 𝐵) |
| 105 | | mnfxr 8083 |
. . . . . . . . 9
⊢ -∞
∈ ℝ* |
| 106 | | xrltnr 9854 |
. . . . . . . . 9
⊢ (-∞
∈ ℝ* → ¬ -∞ <
-∞) |
| 107 | 105, 106 | ax-mp 5 |
. . . . . . . 8
⊢ ¬
-∞ < -∞ |
| 108 | | breq12 4038 |
. . . . . . . . 9
⊢ ((𝐴 = -∞ ∧ 𝐵 = -∞) → (𝐴 < 𝐵 ↔ -∞ <
-∞)) |
| 109 | 108 | ancoms 268 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 = -∞) → (𝐴 < 𝐵 ↔ -∞ <
-∞)) |
| 110 | 107, 109 | mtbiri 676 |
. . . . . . 7
⊢ ((𝐵 = -∞ ∧ 𝐴 = -∞) → ¬ 𝐴 < 𝐵) |
| 111 | | breq12 4038 |
. . . . . . . 8
⊢ ((𝐵 = -∞ ∧ 𝐴 = -∞) → (𝐵 < 𝐴 ↔ -∞ <
-∞)) |
| 112 | 107, 111 | mtbiri 676 |
. . . . . . 7
⊢ ((𝐵 = -∞ ∧ 𝐴 = -∞) → ¬ 𝐵 < 𝐴) |
| 113 | 110, 112 | jca 306 |
. . . . . 6
⊢ ((𝐵 = -∞ ∧ 𝐴 = -∞) → (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴)) |
| 114 | 104, 113 | 2thd 175 |
. . . . 5
⊢ ((𝐵 = -∞ ∧ 𝐴 = -∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 115 | 92, 102, 114 | 3jaodan 1317 |
. . . 4
⊢ ((𝐵 = -∞ ∧ (𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞)) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 116 | 115 | ancoms 268 |
. . 3
⊢ (((𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞) ∧ 𝐵 = -∞) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 117 | 40, 79, 116 | 3jaodan 1317 |
. 2
⊢ (((𝐴 ∈ ℝ ∨ 𝐴 = +∞ ∨ 𝐴 = -∞) ∧ (𝐵 ∈ ℝ ∨ 𝐵 = +∞ ∨ 𝐵 = -∞)) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |
| 118 | 1, 2, 117 | syl2anb 291 |
1
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (𝐴 = 𝐵 ↔ (¬ 𝐴 < 𝐵 ∧ ¬ 𝐵 < 𝐴))) |