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Mathbox for Asger C. Ipsen |
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Mirrors > Home > MPE Home > Th. List > Mathboxes > dnizeq0 | Structured version Visualization version GIF version |
Description: The distance to nearest integer is zero for integers. (Contributed by Asger C. Ipsen, 15-Jun-2021.) |
Ref | Expression |
---|---|
dnizeq0.t | ⊢ 𝑇 = (𝑥 ∈ ℝ ↦ (abs‘((⌊‘(𝑥 + (1 / 2))) − 𝑥))) |
dnizeq0.1 | ⊢ (𝜑 → 𝐴 ∈ ℤ) |
Ref | Expression |
---|---|
dnizeq0 | ⊢ (𝜑 → (𝑇‘𝐴) = 0) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | dnizeq0.1 | . . . 4 ⊢ (𝜑 → 𝐴 ∈ ℤ) | |
2 | 1 | zred 12667 | . . 3 ⊢ (𝜑 → 𝐴 ∈ ℝ) |
3 | dnizeq0.t | . . . 4 ⊢ 𝑇 = (𝑥 ∈ ℝ ↦ (abs‘((⌊‘(𝑥 + (1 / 2))) − 𝑥))) | |
4 | 3 | dnival 35854 | . . 3 ⊢ (𝐴 ∈ ℝ → (𝑇‘𝐴) = (abs‘((⌊‘(𝐴 + (1 / 2))) − 𝐴))) |
5 | 2, 4 | syl 17 | . 2 ⊢ (𝜑 → (𝑇‘𝐴) = (abs‘((⌊‘(𝐴 + (1 / 2))) − 𝐴))) |
6 | halfre 12427 | . . . . . . . . . 10 ⊢ (1 / 2) ∈ ℝ | |
7 | 6 | a1i 11 | . . . . . . . . 9 ⊢ (𝜑 → (1 / 2) ∈ ℝ) |
8 | 1, 7 | jca 511 | . . . . . . . 8 ⊢ (𝜑 → (𝐴 ∈ ℤ ∧ (1 / 2) ∈ ℝ)) |
9 | flzadd 13794 | . . . . . . . 8 ⊢ ((𝐴 ∈ ℤ ∧ (1 / 2) ∈ ℝ) → (⌊‘(𝐴 + (1 / 2))) = (𝐴 + (⌊‘(1 / 2)))) | |
10 | 8, 9 | syl 17 | . . . . . . 7 ⊢ (𝜑 → (⌊‘(𝐴 + (1 / 2))) = (𝐴 + (⌊‘(1 / 2)))) |
11 | 6 | rexri 11273 | . . . . . . . . . . . . 13 ⊢ (1 / 2) ∈ ℝ* |
12 | 0re 11217 | . . . . . . . . . . . . . 14 ⊢ 0 ∈ ℝ | |
13 | halfgt0 12429 | . . . . . . . . . . . . . 14 ⊢ 0 < (1 / 2) | |
14 | 12, 6, 13 | ltleii 11338 | . . . . . . . . . . . . 13 ⊢ 0 ≤ (1 / 2) |
15 | halflt1 12431 | . . . . . . . . . . . . 13 ⊢ (1 / 2) < 1 | |
16 | 11, 14, 15 | 3pm3.2i 1336 | . . . . . . . . . . . 12 ⊢ ((1 / 2) ∈ ℝ* ∧ 0 ≤ (1 / 2) ∧ (1 / 2) < 1) |
17 | 0xr 11262 | . . . . . . . . . . . . . 14 ⊢ 0 ∈ ℝ* | |
18 | 1xr 11274 | . . . . . . . . . . . . . 14 ⊢ 1 ∈ ℝ* | |
19 | 17, 18 | pm3.2i 470 | . . . . . . . . . . . . 13 ⊢ (0 ∈ ℝ* ∧ 1 ∈ ℝ*) |
20 | elico1 13370 | . . . . . . . . . . . . 13 ⊢ ((0 ∈ ℝ* ∧ 1 ∈ ℝ*) → ((1 / 2) ∈ (0[,)1) ↔ ((1 / 2) ∈ ℝ* ∧ 0 ≤ (1 / 2) ∧ (1 / 2) < 1))) | |
21 | 19, 20 | ax-mp 5 | . . . . . . . . . . . 12 ⊢ ((1 / 2) ∈ (0[,)1) ↔ ((1 / 2) ∈ ℝ* ∧ 0 ≤ (1 / 2) ∧ (1 / 2) < 1)) |
22 | 16, 21 | mpbir 230 | . . . . . . . . . . 11 ⊢ (1 / 2) ∈ (0[,)1) |
23 | 22 | a1i 11 | . . . . . . . . . 10 ⊢ (𝜑 → (1 / 2) ∈ (0[,)1)) |
24 | ico01fl0 13787 | . . . . . . . . . 10 ⊢ ((1 / 2) ∈ (0[,)1) → (⌊‘(1 / 2)) = 0) | |
25 | 23, 24 | syl 17 | . . . . . . . . 9 ⊢ (𝜑 → (⌊‘(1 / 2)) = 0) |
26 | 25 | oveq2d 7420 | . . . . . . . 8 ⊢ (𝜑 → (𝐴 + (⌊‘(1 / 2))) = (𝐴 + 0)) |
27 | 2 | recnd 11243 | . . . . . . . . 9 ⊢ (𝜑 → 𝐴 ∈ ℂ) |
28 | 27 | addridd 11415 | . . . . . . . 8 ⊢ (𝜑 → (𝐴 + 0) = 𝐴) |
29 | 26, 28 | eqtrd 2766 | . . . . . . 7 ⊢ (𝜑 → (𝐴 + (⌊‘(1 / 2))) = 𝐴) |
30 | 10, 29 | eqtrd 2766 | . . . . . 6 ⊢ (𝜑 → (⌊‘(𝐴 + (1 / 2))) = 𝐴) |
31 | 30 | oveq1d 7419 | . . . . 5 ⊢ (𝜑 → ((⌊‘(𝐴 + (1 / 2))) − 𝐴) = (𝐴 − 𝐴)) |
32 | 27 | subidd 11560 | . . . . 5 ⊢ (𝜑 → (𝐴 − 𝐴) = 0) |
33 | 31, 32 | eqtrd 2766 | . . . 4 ⊢ (𝜑 → ((⌊‘(𝐴 + (1 / 2))) − 𝐴) = 0) |
34 | 33 | fveq2d 6888 | . . 3 ⊢ (𝜑 → (abs‘((⌊‘(𝐴 + (1 / 2))) − 𝐴)) = (abs‘0)) |
35 | abs0 15235 | . . . 4 ⊢ (abs‘0) = 0 | |
36 | 35 | a1i 11 | . . 3 ⊢ (𝜑 → (abs‘0) = 0) |
37 | 34, 36 | eqtrd 2766 | . 2 ⊢ (𝜑 → (abs‘((⌊‘(𝐴 + (1 / 2))) − 𝐴)) = 0) |
38 | 5, 37 | eqtrd 2766 | 1 ⊢ (𝜑 → (𝑇‘𝐴) = 0) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ↔ wb 205 ∧ wa 395 ∧ w3a 1084 = wceq 1533 ∈ wcel 2098 class class class wbr 5141 ↦ cmpt 5224 ‘cfv 6536 (class class class)co 7404 ℝcr 11108 0cc0 11109 1c1 11110 + caddc 11112 ℝ*cxr 11248 < clt 11249 ≤ cle 11250 − cmin 11445 / cdiv 11872 2c2 12268 ℤcz 12559 [,)cico 13329 ⌊cfl 13758 abscabs 15184 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1789 ax-4 1803 ax-5 1905 ax-6 1963 ax-7 2003 ax-8 2100 ax-9 2108 ax-10 2129 ax-11 2146 ax-12 2163 ax-ext 2697 ax-sep 5292 ax-nul 5299 ax-pow 5356 ax-pr 5420 ax-un 7721 ax-cnex 11165 ax-resscn 11166 ax-1cn 11167 ax-icn 11168 ax-addcl 11169 ax-addrcl 11170 ax-mulcl 11171 ax-mulrcl 11172 ax-mulcom 11173 ax-addass 11174 ax-mulass 11175 ax-distr 11176 ax-i2m1 11177 ax-1ne0 11178 ax-1rid 11179 ax-rnegex 11180 ax-rrecex 11181 ax-cnre 11182 ax-pre-lttri 11183 ax-pre-lttrn 11184 ax-pre-ltadd 11185 ax-pre-mulgt0 11186 ax-pre-sup 11187 |
This theorem depends on definitions: df-bi 206 df-an 396 df-or 845 df-3or 1085 df-3an 1086 df-tru 1536 df-fal 1546 df-ex 1774 df-nf 1778 df-sb 2060 df-mo 2528 df-eu 2557 df-clab 2704 df-cleq 2718 df-clel 2804 df-nfc 2879 df-ne 2935 df-nel 3041 df-ral 3056 df-rex 3065 df-rmo 3370 df-reu 3371 df-rab 3427 df-v 3470 df-sbc 3773 df-csb 3889 df-dif 3946 df-un 3948 df-in 3950 df-ss 3960 df-pss 3962 df-nul 4318 df-if 4524 df-pw 4599 df-sn 4624 df-pr 4626 df-op 4630 df-uni 4903 df-iun 4992 df-br 5142 df-opab 5204 df-mpt 5225 df-tr 5259 df-id 5567 df-eprel 5573 df-po 5581 df-so 5582 df-fr 5624 df-we 5626 df-xp 5675 df-rel 5676 df-cnv 5677 df-co 5678 df-dm 5679 df-rn 5680 df-res 5681 df-ima 5682 df-pred 6293 df-ord 6360 df-on 6361 df-lim 6362 df-suc 6363 df-iota 6488 df-fun 6538 df-fn 6539 df-f 6540 df-f1 6541 df-fo 6542 df-f1o 6543 df-fv 6544 df-riota 7360 df-ov 7407 df-oprab 7408 df-mpo 7409 df-om 7852 df-2nd 7972 df-frecs 8264 df-wrecs 8295 df-recs 8369 df-rdg 8408 df-er 8702 df-en 8939 df-dom 8940 df-sdom 8941 df-sup 9436 df-inf 9437 df-pnf 11251 df-mnf 11252 df-xr 11253 df-ltxr 11254 df-le 11255 df-sub 11447 df-neg 11448 df-div 11873 df-nn 12214 df-2 12276 df-n0 12474 df-z 12560 df-uz 12824 df-rp 12978 df-ico 13333 df-fl 13760 df-seq 13970 df-exp 14030 df-cj 15049 df-re 15050 df-im 15051 df-sqrt 15185 df-abs 15186 |
This theorem is referenced by: knoppndvlem6 35900 knoppndvlem8 35902 |
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