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Mathbox for Thierry Arnoux |
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Mirrors > Home > MPE Home > Th. List > Mathboxes > sgnsval | Structured version Visualization version GIF version |
Description: The sign value. (Contributed by Thierry Arnoux, 9-Sep-2018.) |
Ref | Expression |
---|---|
sgnsval.b | ⊢ 𝐵 = (Base‘𝑅) |
sgnsval.0 | ⊢ 0 = (0g‘𝑅) |
sgnsval.l | ⊢ < = (lt‘𝑅) |
sgnsval.s | ⊢ 𝑆 = (sgns‘𝑅) |
Ref | Expression |
---|---|
sgnsval | ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → (𝑆‘𝑋) = if(𝑋 = 0 , 0, if( 0 < 𝑋, 1, -1))) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sgnsval.b | . . . 4 ⊢ 𝐵 = (Base‘𝑅) | |
2 | sgnsval.0 | . . . 4 ⊢ 0 = (0g‘𝑅) | |
3 | sgnsval.l | . . . 4 ⊢ < = (lt‘𝑅) | |
4 | sgnsval.s | . . . 4 ⊢ 𝑆 = (sgns‘𝑅) | |
5 | 1, 2, 3, 4 | sgnsv 32822 | . . 3 ⊢ (𝑅 ∈ 𝑉 → 𝑆 = (𝑥 ∈ 𝐵 ↦ if(𝑥 = 0 , 0, if( 0 < 𝑥, 1, -1)))) |
6 | 5 | adantr 480 | . 2 ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → 𝑆 = (𝑥 ∈ 𝐵 ↦ if(𝑥 = 0 , 0, if( 0 < 𝑥, 1, -1)))) |
7 | eqeq1 2730 | . . . 4 ⊢ (𝑥 = 𝑋 → (𝑥 = 0 ↔ 𝑋 = 0 )) | |
8 | breq2 5145 | . . . . 5 ⊢ (𝑥 = 𝑋 → ( 0 < 𝑥 ↔ 0 < 𝑋)) | |
9 | 8 | ifbid 4546 | . . . 4 ⊢ (𝑥 = 𝑋 → if( 0 < 𝑥, 1, -1) = if( 0 < 𝑋, 1, -1)) |
10 | 7, 9 | ifbieq2d 4549 | . . 3 ⊢ (𝑥 = 𝑋 → if(𝑥 = 0 , 0, if( 0 < 𝑥, 1, -1)) = if(𝑋 = 0 , 0, if( 0 < 𝑋, 1, -1))) |
11 | 10 | adantl 481 | . 2 ⊢ (((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ 𝑥 = 𝑋) → if(𝑥 = 0 , 0, if( 0 < 𝑥, 1, -1)) = if(𝑋 = 0 , 0, if( 0 < 𝑋, 1, -1))) |
12 | simpr 484 | . 2 ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → 𝑋 ∈ 𝐵) | |
13 | c0ex 11209 | . . . 4 ⊢ 0 ∈ V | |
14 | 13 | a1i 11 | . . 3 ⊢ (((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ 𝑋 = 0 ) → 0 ∈ V) |
15 | 1ex 11211 | . . . . 5 ⊢ 1 ∈ V | |
16 | 15 | a1i 11 | . . . 4 ⊢ ((((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ ¬ 𝑋 = 0 ) ∧ 0 < 𝑋) → 1 ∈ V) |
17 | negex 11459 | . . . . 5 ⊢ -1 ∈ V | |
18 | 17 | a1i 11 | . . . 4 ⊢ ((((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ ¬ 𝑋 = 0 ) ∧ ¬ 0 < 𝑋) → -1 ∈ V) |
19 | 16, 18 | ifclda 4558 | . . 3 ⊢ (((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ ¬ 𝑋 = 0 ) → if( 0 < 𝑋, 1, -1) ∈ V) |
20 | 14, 19 | ifclda 4558 | . 2 ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → if(𝑋 = 0 , 0, if( 0 < 𝑋, 1, -1)) ∈ V) |
21 | 6, 11, 12, 20 | fvmptd 6998 | 1 ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → (𝑆‘𝑋) = if(𝑋 = 0 , 0, if( 0 < 𝑋, 1, -1))) |
Colors of variables: wff setvar class |
Syntax hints: ¬ wn 3 → wi 4 ∧ wa 395 = wceq 1533 ∈ wcel 2098 Vcvv 3468 ifcif 4523 class class class wbr 5141 ↦ cmpt 5224 ‘cfv 6536 0cc0 11109 1c1 11110 -cneg 11446 Basecbs 17150 0gc0g 17391 ltcplt 18270 sgnscsgns 32820 |
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-rep 5278 ax-sep 5292 ax-nul 5299 ax-pr 5420 ax-1cn 11167 ax-icn 11168 ax-addcl 11169 ax-mulcl 11171 ax-i2m1 11177 |
This theorem depends on definitions: df-bi 206 df-an 396 df-or 845 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-ral 3056 df-rex 3065 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-nul 4318 df-if 4524 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-id 5567 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-iota 6488 df-fun 6538 df-fn 6539 df-f 6540 df-f1 6541 df-fo 6542 df-f1o 6543 df-fv 6544 df-ov 7407 df-neg 11448 df-sgns 32821 |
This theorem is referenced by: (None) |
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