![]() |
Mathbox for Thierry Arnoux |
< Previous
Next >
Nearby theorems |
|
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 32058 | . . 3 ⊢ (𝑅 ∈ 𝑉 → 𝑆 = (𝑥 ∈ 𝐵 ↦ if(𝑥 = 0 , 0, if( 0 < 𝑥, 1, -1)))) |
6 | 5 | adantr 482 | . 2 ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → 𝑆 = (𝑥 ∈ 𝐵 ↦ if(𝑥 = 0 , 0, if( 0 < 𝑥, 1, -1)))) |
7 | eqeq1 2737 | . . . 4 ⊢ (𝑥 = 𝑋 → (𝑥 = 0 ↔ 𝑋 = 0 )) | |
8 | breq2 5110 | . . . . 5 ⊢ (𝑥 = 𝑋 → ( 0 < 𝑥 ↔ 0 < 𝑋)) | |
9 | 8 | ifbid 4510 | . . . 4 ⊢ (𝑥 = 𝑋 → if( 0 < 𝑥, 1, -1) = if( 0 < 𝑋, 1, -1)) |
10 | 7, 9 | ifbieq2d 4513 | . . 3 ⊢ (𝑥 = 𝑋 → if(𝑥 = 0 , 0, if( 0 < 𝑥, 1, -1)) = if(𝑋 = 0 , 0, if( 0 < 𝑋, 1, -1))) |
11 | 10 | adantl 483 | . 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 486 | . 2 ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → 𝑋 ∈ 𝐵) | |
13 | c0ex 11154 | . . . 4 ⊢ 0 ∈ V | |
14 | 13 | a1i 11 | . . 3 ⊢ (((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ 𝑋 = 0 ) → 0 ∈ V) |
15 | 1ex 11156 | . . . . 5 ⊢ 1 ∈ V | |
16 | 15 | a1i 11 | . . . 4 ⊢ ((((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ ¬ 𝑋 = 0 ) ∧ 0 < 𝑋) → 1 ∈ V) |
17 | negex 11404 | . . . . 5 ⊢ -1 ∈ V | |
18 | 17 | a1i 11 | . . . 4 ⊢ ((((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ ¬ 𝑋 = 0 ) ∧ ¬ 0 < 𝑋) → -1 ∈ V) |
19 | 16, 18 | ifclda 4522 | . . 3 ⊢ (((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) ∧ ¬ 𝑋 = 0 ) → if( 0 < 𝑋, 1, -1) ∈ V) |
20 | 14, 19 | ifclda 4522 | . 2 ⊢ ((𝑅 ∈ 𝑉 ∧ 𝑋 ∈ 𝐵) → if(𝑋 = 0 , 0, if( 0 < 𝑋, 1, -1)) ∈ V) |
21 | 6, 11, 12, 20 | fvmptd 6956 | 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 397 = wceq 1542 ∈ wcel 2107 Vcvv 3444 ifcif 4487 class class class wbr 5106 ↦ cmpt 5189 ‘cfv 6497 0cc0 11056 1c1 11057 -cneg 11391 Basecbs 17088 0gc0g 17326 ltcplt 18202 sgnscsgns 32056 |
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 5243 ax-sep 5257 ax-nul 5264 ax-pr 5385 ax-1cn 11114 ax-icn 11115 ax-addcl 11116 ax-mulcl 11118 ax-i2m1 11124 |
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 2941 df-ral 3062 df-rex 3071 df-reu 3353 df-rab 3407 df-v 3446 df-sbc 3741 df-csb 3857 df-dif 3914 df-un 3916 df-in 3918 df-ss 3928 df-nul 4284 df-if 4488 df-sn 4588 df-pr 4590 df-op 4594 df-uni 4867 df-iun 4957 df-br 5107 df-opab 5169 df-mpt 5190 df-id 5532 df-xp 5640 df-rel 5641 df-cnv 5642 df-co 5643 df-dm 5644 df-rn 5645 df-res 5646 df-ima 5647 df-iota 6449 df-fun 6499 df-fn 6500 df-f 6501 df-f1 6502 df-fo 6503 df-f1o 6504 df-fv 6505 df-ov 7361 df-neg 11393 df-sgns 32057 |
This theorem is referenced by: (None) |
Copyright terms: Public domain | W3C validator |