![]() |
Mathbox for BJ |
< Previous
Next >
Nearby theorems |
|
Mirrors > Home > MPE Home > Th. List > Mathboxes > bj-rest0 | Structured version Visualization version GIF version |
Description: An elementwise intersection on a family containing the empty set contains the empty set. (Contributed by BJ, 27-Apr-2021.) |
Ref | Expression |
---|---|
bj-rest0 | ⊢ ((𝑋 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (∅ ∈ 𝑋 → ∅ ∈ (𝑋 ↾t 𝐴))) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | in0 4389 | . . . . 5 ⊢ (𝐴 ∩ ∅) = ∅ | |
2 | incom 4199 | . . . . 5 ⊢ (𝐴 ∩ ∅) = (∅ ∩ 𝐴) | |
3 | 1, 2 | eqtr3i 2763 | . . . 4 ⊢ ∅ = (∅ ∩ 𝐴) |
4 | 0ex 5305 | . . . . 5 ⊢ ∅ ∈ V | |
5 | eleq1 2822 | . . . . . 6 ⊢ (𝑥 = ∅ → (𝑥 ∈ 𝑋 ↔ ∅ ∈ 𝑋)) | |
6 | ineq1 4203 | . . . . . . 7 ⊢ (𝑥 = ∅ → (𝑥 ∩ 𝐴) = (∅ ∩ 𝐴)) | |
7 | 6 | eqeq2d 2744 | . . . . . 6 ⊢ (𝑥 = ∅ → (∅ = (𝑥 ∩ 𝐴) ↔ ∅ = (∅ ∩ 𝐴))) |
8 | 5, 7 | anbi12d 632 | . . . . 5 ⊢ (𝑥 = ∅ → ((𝑥 ∈ 𝑋 ∧ ∅ = (𝑥 ∩ 𝐴)) ↔ (∅ ∈ 𝑋 ∧ ∅ = (∅ ∩ 𝐴)))) |
9 | 4, 8 | spcev 3595 | . . . 4 ⊢ ((∅ ∈ 𝑋 ∧ ∅ = (∅ ∩ 𝐴)) → ∃𝑥(𝑥 ∈ 𝑋 ∧ ∅ = (𝑥 ∩ 𝐴))) |
10 | 3, 9 | mpan2 690 | . . 3 ⊢ (∅ ∈ 𝑋 → ∃𝑥(𝑥 ∈ 𝑋 ∧ ∅ = (𝑥 ∩ 𝐴))) |
11 | df-rex 3072 | . . 3 ⊢ (∃𝑥 ∈ 𝑋 ∅ = (𝑥 ∩ 𝐴) ↔ ∃𝑥(𝑥 ∈ 𝑋 ∧ ∅ = (𝑥 ∩ 𝐴))) | |
12 | 10, 11 | sylibr 233 | . 2 ⊢ (∅ ∈ 𝑋 → ∃𝑥 ∈ 𝑋 ∅ = (𝑥 ∩ 𝐴)) |
13 | elrest 17368 | . 2 ⊢ ((𝑋 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (∅ ∈ (𝑋 ↾t 𝐴) ↔ ∃𝑥 ∈ 𝑋 ∅ = (𝑥 ∩ 𝐴))) | |
14 | 12, 13 | imbitrrid 245 | 1 ⊢ ((𝑋 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (∅ ∈ 𝑋 → ∅ ∈ (𝑋 ↾t 𝐴))) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∧ wa 397 = wceq 1542 ∃wex 1782 ∈ wcel 2107 ∃wrex 3071 ∩ cin 3945 ∅c0 4320 (class class class)co 7403 ↾t crest 17361 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1798 ax-4 1812 ax-5 1914 ax-6 1972 ax-7 2012 ax-8 2109 ax-9 2117 ax-10 2138 ax-11 2155 ax-12 2172 ax-ext 2704 ax-rep 5283 ax-sep 5297 ax-nul 5304 ax-pr 5425 ax-un 7719 |
This theorem depends on definitions: df-bi 206 df-an 398 df-or 847 df-3an 1090 df-tru 1545 df-fal 1555 df-ex 1783 df-nf 1787 df-sb 2069 df-mo 2535 df-eu 2564 df-clab 2711 df-cleq 2725 df-clel 2811 df-nfc 2886 df-ne 2942 df-ral 3063 df-rex 3072 df-reu 3378 df-rab 3434 df-v 3477 df-sbc 3776 df-csb 3892 df-dif 3949 df-un 3951 df-in 3953 df-ss 3963 df-nul 4321 df-if 4527 df-sn 4627 df-pr 4629 df-op 4633 df-uni 4907 df-iun 4997 df-br 5147 df-opab 5209 df-mpt 5230 df-id 5572 df-xp 5680 df-rel 5681 df-cnv 5682 df-co 5683 df-dm 5684 df-rn 5685 df-res 5686 df-ima 5687 df-iota 6491 df-fun 6541 df-fn 6542 df-f 6543 df-f1 6544 df-fo 6545 df-f1o 6546 df-fv 6547 df-ov 7406 df-oprab 7407 df-mpo 7408 df-rest 17363 |
This theorem is referenced by: (None) |
Copyright terms: Public domain | W3C validator |