| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | iocval 13425 | . . 3
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (𝐴(,]𝐵) = {𝑥 ∈ ℝ* ∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)}) | 
| 2 | 1 | eqeq1d 2738 | . 2
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → ((𝐴(,]𝐵) = ∅ ↔ {𝑥 ∈ ℝ* ∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} = ∅)) | 
| 3 |  | df-ne 2940 | . . . . . 6
⊢ ({𝑥 ∈ ℝ*
∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} ≠ ∅ ↔ ¬ {𝑥 ∈ ℝ*
∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} = ∅) | 
| 4 |  | rabn0 4388 | . . . . . 6
⊢ ({𝑥 ∈ ℝ*
∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} ≠ ∅ ↔ ∃𝑥 ∈ ℝ*
(𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)) | 
| 5 | 3, 4 | bitr3i 277 | . . . . 5
⊢ (¬
{𝑥 ∈
ℝ* ∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} = ∅ ↔ ∃𝑥 ∈ ℝ*
(𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)) | 
| 6 |  | xrltletr 13200 | . . . . . . . . 9
⊢ ((𝐴 ∈ ℝ*
∧ 𝑥 ∈
ℝ* ∧ 𝐵
∈ ℝ*) → ((𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵) → 𝐴 < 𝐵)) | 
| 7 | 6 | 3com23 1126 | . . . . . . . 8
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ* ∧ 𝑥
∈ ℝ*) → ((𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵) → 𝐴 < 𝐵)) | 
| 8 | 7 | 3expa 1118 | . . . . . . 7
⊢ (((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) ∧ 𝑥 ∈ ℝ*) → ((𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵) → 𝐴 < 𝐵)) | 
| 9 | 8 | rexlimdva 3154 | . . . . . 6
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (∃𝑥 ∈ ℝ* (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵) → 𝐴 < 𝐵)) | 
| 10 |  | qbtwnxr 13243 | . . . . . . . 8
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ* ∧ 𝐴
< 𝐵) → ∃𝑥 ∈ ℚ (𝐴 < 𝑥 ∧ 𝑥 < 𝐵)) | 
| 11 |  | qre 12996 | . . . . . . . . . . . . 13
⊢ (𝑥 ∈ ℚ → 𝑥 ∈
ℝ) | 
| 12 | 11 | rexrd 11312 | . . . . . . . . . . . 12
⊢ (𝑥 ∈ ℚ → 𝑥 ∈
ℝ*) | 
| 13 | 12 | a1i 11 | . . . . . . . . . . . . . 14
⊢ ((𝑥 ∈ ℝ*
∧ (𝐴 ∈
ℝ* ∧ 𝐵
∈ ℝ* ∧ 𝐴 < 𝐵)) → (𝑥 ∈ ℚ → 𝑥 ∈
ℝ*)) | 
| 14 |  | xrltle 13192 | . . . . . . . . . . . . . . . 16
⊢ ((𝑥 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (𝑥 < 𝐵 → 𝑥 ≤ 𝐵)) | 
| 15 | 14 | 3ad2antr2 1189 | . . . . . . . . . . . . . . 15
⊢ ((𝑥 ∈ ℝ*
∧ (𝐴 ∈
ℝ* ∧ 𝐵
∈ ℝ* ∧ 𝐴 < 𝐵)) → (𝑥 < 𝐵 → 𝑥 ≤ 𝐵)) | 
| 16 | 15 | anim2d 612 | . . . . . . . . . . . . . 14
⊢ ((𝑥 ∈ ℝ*
∧ (𝐴 ∈
ℝ* ∧ 𝐵
∈ ℝ* ∧ 𝐴 < 𝐵)) → ((𝐴 < 𝑥 ∧ 𝑥 < 𝐵) → (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵))) | 
| 17 | 13, 16 | anim12d 609 | . . . . . . . . . . . . 13
⊢ ((𝑥 ∈ ℝ*
∧ (𝐴 ∈
ℝ* ∧ 𝐵
∈ ℝ* ∧ 𝐴 < 𝐵)) → ((𝑥 ∈ ℚ ∧ (𝐴 < 𝑥 ∧ 𝑥 < 𝐵)) → (𝑥 ∈ ℝ* ∧ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)))) | 
| 18 | 17 | ex 412 | . . . . . . . . . . . 12
⊢ (𝑥 ∈ ℝ*
→ ((𝐴 ∈
ℝ* ∧ 𝐵
∈ ℝ* ∧ 𝐴 < 𝐵) → ((𝑥 ∈ ℚ ∧ (𝐴 < 𝑥 ∧ 𝑥 < 𝐵)) → (𝑥 ∈ ℝ* ∧ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵))))) | 
| 19 | 12, 18 | syl 17 | . . . . . . . . . . 11
⊢ (𝑥 ∈ ℚ → ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ* ∧ 𝐴
< 𝐵) → ((𝑥 ∈ ℚ ∧ (𝐴 < 𝑥 ∧ 𝑥 < 𝐵)) → (𝑥 ∈ ℝ* ∧ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵))))) | 
| 20 | 19 | adantr 480 | . . . . . . . . . 10
⊢ ((𝑥 ∈ ℚ ∧ (𝐴 < 𝑥 ∧ 𝑥 < 𝐵)) → ((𝐴 ∈ ℝ* ∧ 𝐵 ∈ ℝ*
∧ 𝐴 < 𝐵) → ((𝑥 ∈ ℚ ∧ (𝐴 < 𝑥 ∧ 𝑥 < 𝐵)) → (𝑥 ∈ ℝ* ∧ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵))))) | 
| 21 | 20 | pm2.43b 55 | . . . . . . . . 9
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ* ∧ 𝐴
< 𝐵) → ((𝑥 ∈ ℚ ∧ (𝐴 < 𝑥 ∧ 𝑥 < 𝐵)) → (𝑥 ∈ ℝ* ∧ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)))) | 
| 22 | 21 | reximdv2 3163 | . . . . . . . 8
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ* ∧ 𝐴
< 𝐵) →
(∃𝑥 ∈ ℚ
(𝐴 < 𝑥 ∧ 𝑥 < 𝐵) → ∃𝑥 ∈ ℝ* (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵))) | 
| 23 | 10, 22 | mpd 15 | . . . . . . 7
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ* ∧ 𝐴
< 𝐵) → ∃𝑥 ∈ ℝ*
(𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)) | 
| 24 | 23 | 3expia 1121 | . . . . . 6
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (𝐴 < 𝐵 → ∃𝑥 ∈ ℝ* (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵))) | 
| 25 | 9, 24 | impbid 212 | . . . . 5
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (∃𝑥 ∈ ℝ* (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵) ↔ 𝐴 < 𝐵)) | 
| 26 | 5, 25 | bitrid 283 | . . . 4
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (¬ {𝑥 ∈ ℝ* ∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} = ∅ ↔ 𝐴 < 𝐵)) | 
| 27 |  | xrltnle 11329 | . . . 4
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (𝐴 < 𝐵 ↔ ¬ 𝐵 ≤ 𝐴)) | 
| 28 | 26, 27 | bitrd 279 | . . 3
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → (¬ {𝑥 ∈ ℝ* ∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} = ∅ ↔ ¬ 𝐵 ≤ 𝐴)) | 
| 29 | 28 | con4bid 317 | . 2
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → ({𝑥 ∈ ℝ* ∣ (𝐴 < 𝑥 ∧ 𝑥 ≤ 𝐵)} = ∅ ↔ 𝐵 ≤ 𝐴)) | 
| 30 | 2, 29 | bitrd 279 | 1
⊢ ((𝐴 ∈ ℝ*
∧ 𝐵 ∈
ℝ*) → ((𝐴(,]𝐵) = ∅ ↔ 𝐵 ≤ 𝐴)) |