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Description: The topology of the extended reals. (Contributed by Mario Carneiro, 3-Sep-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | leordtval.1 | ⊢ 𝐴 = ran ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) | |
| leordtval.2 | ⊢ 𝐵 = ran ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) | ||
| Assertion | leordtval2 | ⊢ ( ordTop ‘ ≤ ) = ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | leordtval.1 | ⊢ 𝐴 = ran ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) | |
| 2 | leordtval.2 | ⊢ 𝐵 = ran ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) | |
| 3 | letsr | ⊢ ≤ ∈ TosetRel | |
| 4 | ledm | ⊢ ℝ* = dom ≤ | |
| 5 | 1 | leordtvallem1 | ⊢ 𝐴 = ran ( 𝑥 ∈ ℝ* ↦ { 𝑦 ∈ ℝ* ∣ ¬ 𝑦 ≤ 𝑥 } ) |
| 6 | 1 2 | leordtvallem2 | ⊢ 𝐵 = ran ( 𝑥 ∈ ℝ* ↦ { 𝑦 ∈ ℝ* ∣ ¬ 𝑥 ≤ 𝑦 } ) |
| 7 | 4 5 6 | ordtval | ⊢ ( ≤ ∈ TosetRel → ( ordTop ‘ ≤ ) = ( topGen ‘ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ) ) |
| 8 | 3 7 | ax-mp | ⊢ ( ordTop ‘ ≤ ) = ( topGen ‘ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ) |
| 9 | snex | ⊢ { ℝ* } ∈ V | |
| 10 | xrex | ⊢ ℝ* ∈ V | |
| 11 | 10 | pwex | ⊢ 𝒫 ℝ* ∈ V |
| 12 | eqid | ⊢ ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) = ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) | |
| 13 | iocssxr | ⊢ ( 𝑥 (,] +∞ ) ⊆ ℝ* | |
| 14 | 10 13 | elpwi2 | ⊢ ( 𝑥 (,] +∞ ) ∈ 𝒫 ℝ* |
| 15 | 14 | a1i | ⊢ ( 𝑥 ∈ ℝ* → ( 𝑥 (,] +∞ ) ∈ 𝒫 ℝ* ) |
| 16 | 12 15 | fmpti | ⊢ ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) : ℝ* ⟶ 𝒫 ℝ* |
| 17 | frn | ⊢ ( ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) : ℝ* ⟶ 𝒫 ℝ* → ran ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) ⊆ 𝒫 ℝ* ) | |
| 18 | 16 17 | ax-mp | ⊢ ran ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) ⊆ 𝒫 ℝ* |
| 19 | 1 18 | eqsstri | ⊢ 𝐴 ⊆ 𝒫 ℝ* |
| 20 | eqid | ⊢ ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) = ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) | |
| 21 | icossxr | ⊢ ( -∞ [,) 𝑥 ) ⊆ ℝ* | |
| 22 | 10 21 | elpwi2 | ⊢ ( -∞ [,) 𝑥 ) ∈ 𝒫 ℝ* |
| 23 | 22 | a1i | ⊢ ( 𝑥 ∈ ℝ* → ( -∞ [,) 𝑥 ) ∈ 𝒫 ℝ* ) |
| 24 | 20 23 | fmpti | ⊢ ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) : ℝ* ⟶ 𝒫 ℝ* |
| 25 | frn | ⊢ ( ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) : ℝ* ⟶ 𝒫 ℝ* → ran ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) ⊆ 𝒫 ℝ* ) | |
| 26 | 24 25 | ax-mp | ⊢ ran ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) ⊆ 𝒫 ℝ* |
| 27 | 2 26 | eqsstri | ⊢ 𝐵 ⊆ 𝒫 ℝ* |
| 28 | 19 27 | unssi | ⊢ ( 𝐴 ∪ 𝐵 ) ⊆ 𝒫 ℝ* |
| 29 | 11 28 | ssexi | ⊢ ( 𝐴 ∪ 𝐵 ) ∈ V |
| 30 | 9 29 | unex | ⊢ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ∈ V |
| 31 | ssun2 | ⊢ ( 𝐴 ∪ 𝐵 ) ⊆ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) | |
| 32 | fiss | ⊢ ( ( ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ∈ V ∧ ( 𝐴 ∪ 𝐵 ) ⊆ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) → ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ⊆ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ) | |
| 33 | 30 31 32 | mp2an | ⊢ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ⊆ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) |
| 34 | fvex | ⊢ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ∈ V | |
| 35 | ovex | ⊢ ( 0 (,] +∞ ) ∈ V | |
| 36 | ovex | ⊢ ( -∞ [,) 1 ) ∈ V | |
| 37 | 35 36 | unipr | ⊢ ∪ { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } = ( ( 0 (,] +∞ ) ∪ ( -∞ [,) 1 ) ) |
| 38 | iocssxr | ⊢ ( 0 (,] +∞ ) ⊆ ℝ* | |
| 39 | icossxr | ⊢ ( -∞ [,) 1 ) ⊆ ℝ* | |
| 40 | 38 39 | unssi | ⊢ ( ( 0 (,] +∞ ) ∪ ( -∞ [,) 1 ) ) ⊆ ℝ* |
| 41 | mnfxr | ⊢ -∞ ∈ ℝ* | |
| 42 | 0xr | ⊢ 0 ∈ ℝ* | |
| 43 | pnfxr | ⊢ +∞ ∈ ℝ* | |
| 44 | mnflt0 | ⊢ -∞ < 0 | |
| 45 | 0lepnf | ⊢ 0 ≤ +∞ | |
| 46 | df-icc | ⊢ [,] = ( 𝑥 ∈ ℝ* , 𝑦 ∈ ℝ* ↦ { 𝑧 ∈ ℝ* ∣ ( 𝑥 ≤ 𝑧 ∧ 𝑧 ≤ 𝑦 ) } ) | |
| 47 | df-ioc | ⊢ (,] = ( 𝑥 ∈ ℝ* , 𝑦 ∈ ℝ* ↦ { 𝑧 ∈ ℝ* ∣ ( 𝑥 < 𝑧 ∧ 𝑧 ≤ 𝑦 ) } ) | |
| 48 | xrltnle | ⊢ ( ( 0 ∈ ℝ* ∧ 𝑤 ∈ ℝ* ) → ( 0 < 𝑤 ↔ ¬ 𝑤 ≤ 0 ) ) | |
| 49 | xrletr | ⊢ ( ( 𝑤 ∈ ℝ* ∧ 0 ∈ ℝ* ∧ +∞ ∈ ℝ* ) → ( ( 𝑤 ≤ 0 ∧ 0 ≤ +∞ ) → 𝑤 ≤ +∞ ) ) | |
| 50 | xrlttr | ⊢ ( ( -∞ ∈ ℝ* ∧ 0 ∈ ℝ* ∧ 𝑤 ∈ ℝ* ) → ( ( -∞ < 0 ∧ 0 < 𝑤 ) → -∞ < 𝑤 ) ) | |
| 51 | xrltle | ⊢ ( ( -∞ ∈ ℝ* ∧ 𝑤 ∈ ℝ* ) → ( -∞ < 𝑤 → -∞ ≤ 𝑤 ) ) | |
| 52 | 51 | 3adant2 | ⊢ ( ( -∞ ∈ ℝ* ∧ 0 ∈ ℝ* ∧ 𝑤 ∈ ℝ* ) → ( -∞ < 𝑤 → -∞ ≤ 𝑤 ) ) |
| 53 | 50 52 | syld | ⊢ ( ( -∞ ∈ ℝ* ∧ 0 ∈ ℝ* ∧ 𝑤 ∈ ℝ* ) → ( ( -∞ < 0 ∧ 0 < 𝑤 ) → -∞ ≤ 𝑤 ) ) |
| 54 | 46 47 48 46 49 53 | ixxun | ⊢ ( ( ( -∞ ∈ ℝ* ∧ 0 ∈ ℝ* ∧ +∞ ∈ ℝ* ) ∧ ( -∞ < 0 ∧ 0 ≤ +∞ ) ) → ( ( -∞ [,] 0 ) ∪ ( 0 (,] +∞ ) ) = ( -∞ [,] +∞ ) ) |
| 55 | 44 45 54 | mpanr12 | ⊢ ( ( -∞ ∈ ℝ* ∧ 0 ∈ ℝ* ∧ +∞ ∈ ℝ* ) → ( ( -∞ [,] 0 ) ∪ ( 0 (,] +∞ ) ) = ( -∞ [,] +∞ ) ) |
| 56 | 41 42 43 55 | mp3an | ⊢ ( ( -∞ [,] 0 ) ∪ ( 0 (,] +∞ ) ) = ( -∞ [,] +∞ ) |
| 57 | 1xr | ⊢ 1 ∈ ℝ* | |
| 58 | 0lt1 | ⊢ 0 < 1 | |
| 59 | df-ico | ⊢ [,) = ( 𝑥 ∈ ℝ* , 𝑦 ∈ ℝ* ↦ { 𝑧 ∈ ℝ* ∣ ( 𝑥 ≤ 𝑧 ∧ 𝑧 < 𝑦 ) } ) | |
| 60 | xrlelttr | ⊢ ( ( 𝑤 ∈ ℝ* ∧ 0 ∈ ℝ* ∧ 1 ∈ ℝ* ) → ( ( 𝑤 ≤ 0 ∧ 0 < 1 ) → 𝑤 < 1 ) ) | |
| 61 | 59 46 60 | ixxss2 | ⊢ ( ( 1 ∈ ℝ* ∧ 0 < 1 ) → ( -∞ [,] 0 ) ⊆ ( -∞ [,) 1 ) ) |
| 62 | 57 58 61 | mp2an | ⊢ ( -∞ [,] 0 ) ⊆ ( -∞ [,) 1 ) |
| 63 | unss1 | ⊢ ( ( -∞ [,] 0 ) ⊆ ( -∞ [,) 1 ) → ( ( -∞ [,] 0 ) ∪ ( 0 (,] +∞ ) ) ⊆ ( ( -∞ [,) 1 ) ∪ ( 0 (,] +∞ ) ) ) | |
| 64 | 62 63 | ax-mp | ⊢ ( ( -∞ [,] 0 ) ∪ ( 0 (,] +∞ ) ) ⊆ ( ( -∞ [,) 1 ) ∪ ( 0 (,] +∞ ) ) |
| 65 | 56 64 | eqsstrri | ⊢ ( -∞ [,] +∞ ) ⊆ ( ( -∞ [,) 1 ) ∪ ( 0 (,] +∞ ) ) |
| 66 | iccmax | ⊢ ( -∞ [,] +∞ ) = ℝ* | |
| 67 | uncom | ⊢ ( ( -∞ [,) 1 ) ∪ ( 0 (,] +∞ ) ) = ( ( 0 (,] +∞ ) ∪ ( -∞ [,) 1 ) ) | |
| 68 | 65 66 67 | 3sstr3i | ⊢ ℝ* ⊆ ( ( 0 (,] +∞ ) ∪ ( -∞ [,) 1 ) ) |
| 69 | 40 68 | eqssi | ⊢ ( ( 0 (,] +∞ ) ∪ ( -∞ [,) 1 ) ) = ℝ* |
| 70 | 37 69 | eqtri | ⊢ ∪ { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } = ℝ* |
| 71 | fvex | ⊢ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ∈ V | |
| 72 | ssun1 | ⊢ 𝐴 ⊆ ( 𝐴 ∪ 𝐵 ) | |
| 73 | eqid | ⊢ ( 0 (,] +∞ ) = ( 0 (,] +∞ ) | |
| 74 | oveq1 | ⊢ ( 𝑥 = 0 → ( 𝑥 (,] +∞ ) = ( 0 (,] +∞ ) ) | |
| 75 | 74 | rspceeqv | ⊢ ( ( 0 ∈ ℝ* ∧ ( 0 (,] +∞ ) = ( 0 (,] +∞ ) ) → ∃ 𝑥 ∈ ℝ* ( 0 (,] +∞ ) = ( 𝑥 (,] +∞ ) ) |
| 76 | 42 73 75 | mp2an | ⊢ ∃ 𝑥 ∈ ℝ* ( 0 (,] +∞ ) = ( 𝑥 (,] +∞ ) |
| 77 | ovex | ⊢ ( 𝑥 (,] +∞ ) ∈ V | |
| 78 | 12 77 | elrnmpti | ⊢ ( ( 0 (,] +∞ ) ∈ ran ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) ↔ ∃ 𝑥 ∈ ℝ* ( 0 (,] +∞ ) = ( 𝑥 (,] +∞ ) ) |
| 79 | 76 78 | mpbir | ⊢ ( 0 (,] +∞ ) ∈ ran ( 𝑥 ∈ ℝ* ↦ ( 𝑥 (,] +∞ ) ) |
| 80 | 79 1 | eleqtrri | ⊢ ( 0 (,] +∞ ) ∈ 𝐴 |
| 81 | 72 80 | sselii | ⊢ ( 0 (,] +∞ ) ∈ ( 𝐴 ∪ 𝐵 ) |
| 82 | ssun2 | ⊢ 𝐵 ⊆ ( 𝐴 ∪ 𝐵 ) | |
| 83 | eqid | ⊢ ( -∞ [,) 1 ) = ( -∞ [,) 1 ) | |
| 84 | oveq2 | ⊢ ( 𝑥 = 1 → ( -∞ [,) 𝑥 ) = ( -∞ [,) 1 ) ) | |
| 85 | 84 | rspceeqv | ⊢ ( ( 1 ∈ ℝ* ∧ ( -∞ [,) 1 ) = ( -∞ [,) 1 ) ) → ∃ 𝑥 ∈ ℝ* ( -∞ [,) 1 ) = ( -∞ [,) 𝑥 ) ) |
| 86 | 57 83 85 | mp2an | ⊢ ∃ 𝑥 ∈ ℝ* ( -∞ [,) 1 ) = ( -∞ [,) 𝑥 ) |
| 87 | ovex | ⊢ ( -∞ [,) 𝑥 ) ∈ V | |
| 88 | 20 87 | elrnmpti | ⊢ ( ( -∞ [,) 1 ) ∈ ran ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) ↔ ∃ 𝑥 ∈ ℝ* ( -∞ [,) 1 ) = ( -∞ [,) 𝑥 ) ) |
| 89 | 86 88 | mpbir | ⊢ ( -∞ [,) 1 ) ∈ ran ( 𝑥 ∈ ℝ* ↦ ( -∞ [,) 𝑥 ) ) |
| 90 | 89 2 | eleqtrri | ⊢ ( -∞ [,) 1 ) ∈ 𝐵 |
| 91 | 82 90 | sselii | ⊢ ( -∞ [,) 1 ) ∈ ( 𝐴 ∪ 𝐵 ) |
| 92 | prssi | ⊢ ( ( ( 0 (,] +∞ ) ∈ ( 𝐴 ∪ 𝐵 ) ∧ ( -∞ [,) 1 ) ∈ ( 𝐴 ∪ 𝐵 ) ) → { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } ⊆ ( 𝐴 ∪ 𝐵 ) ) | |
| 93 | 81 91 92 | mp2an | ⊢ { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } ⊆ ( 𝐴 ∪ 𝐵 ) |
| 94 | ssfii | ⊢ ( ( 𝐴 ∪ 𝐵 ) ∈ V → ( 𝐴 ∪ 𝐵 ) ⊆ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) | |
| 95 | 29 94 | ax-mp | ⊢ ( 𝐴 ∪ 𝐵 ) ⊆ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) |
| 96 | 93 95 | sstri | ⊢ { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } ⊆ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) |
| 97 | eltg3i | ⊢ ( ( ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ∈ V ∧ { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } ⊆ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) → ∪ { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } ∈ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) | |
| 98 | 71 96 97 | mp2an | ⊢ ∪ { ( 0 (,] +∞ ) , ( -∞ [,) 1 ) } ∈ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 99 | 70 98 | eqeltrri | ⊢ ℝ* ∈ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 100 | snssi | ⊢ ( ℝ* ∈ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) → { ℝ* } ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) | |
| 101 | 99 100 | ax-mp | ⊢ { ℝ* } ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 102 | bastg | ⊢ ( ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ∈ V → ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) | |
| 103 | 71 102 | ax-mp | ⊢ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 104 | 95 103 | sstri | ⊢ ( 𝐴 ∪ 𝐵 ) ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 105 | 101 104 | unssi | ⊢ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 106 | fiss | ⊢ ( ( ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ∈ V ∧ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) → ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ⊆ ( fi ‘ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) ) | |
| 107 | 34 105 106 | mp2an | ⊢ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ⊆ ( fi ‘ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) |
| 108 | fibas | ⊢ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ∈ TopBases | |
| 109 | tgcl | ⊢ ( ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ∈ TopBases → ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ∈ Top ) | |
| 110 | fitop | ⊢ ( ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ∈ Top → ( fi ‘ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) = ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) | |
| 111 | 108 109 110 | mp2b | ⊢ ( fi ‘ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) = ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 112 | 107 111 | sseqtri | ⊢ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |
| 113 | 2basgen | ⊢ ( ( ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ⊆ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ∧ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ⊆ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) ) → ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) = ( topGen ‘ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ) ) | |
| 114 | 33 112 113 | mp2an | ⊢ ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) = ( topGen ‘ ( fi ‘ ( { ℝ* } ∪ ( 𝐴 ∪ 𝐵 ) ) ) ) |
| 115 | 8 114 | eqtr4i | ⊢ ( ordTop ‘ ≤ ) = ( topGen ‘ ( fi ‘ ( 𝐴 ∪ 𝐵 ) ) ) |