From 009f001cd169467baffdc4f4eed4397dbc823a78 Mon Sep 17 00:00:00 2001 From: Jan Meyer Date: Sat, 7 Mar 2026 10:07:48 +0100 Subject: [PATCH] vault backup: 2026-03-07 10:07:48 --- .obsidian/workspace.json | 19 +++++++++++++++---- DAS/Relations.md | 9 +++++++++ 2 files changed, 24 insertions(+), 4 deletions(-) diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json index 60c9f71..3435719 100644 --- a/.obsidian/workspace.json +++ b/.obsidian/workspace.json @@ -93,7 +93,7 @@ } ], "direction": "horizontal", - "width": 200 + "width": 265.50418853759766 }, "right": { "id": "8a65bc0c1d4d98f2", @@ -163,8 +163,19 @@ "icon": "lucide-list", "title": "Outline" } + }, + { + "id": "7cc839bdf6f45717", + "type": "leaf", + "state": { + "type": "git-view", + "state": {}, + "icon": "git-pull-request", + "title": "Source Control" + } } - ] + ], + "currentTab": 4 } ], "direction": "horizontal", @@ -185,9 +196,9 @@ }, "active": "16b88a8bc6c6b6e0", "lastOpenFiles": [ - "DAS/Relations.md", - "DAS/Set Theory.md", "DAS/Logic.md", + "DAS/Set Theory.md", + "DAS/Relations.md", "DAS/Functions.md", "mathe/notation.md", "Studium.md", diff --git a/DAS/Relations.md b/DAS/Relations.md index 57dc1cd..be2c6b9 100644 --- a/DAS/Relations.md +++ b/DAS/Relations.md @@ -8,6 +8,7 @@ | *symmetric* | the given relation work both ways | $a = b => b = a$ | | *antisymmetric* | the given relation only works both ways if $a$ and $b$ are the same | $a <= b, b <= a => a = b$ | + ## Equivalence Relations A relation $R$ is called _equivalence relation_ when it is _transitive, reflexive and symmetric_. @@ -38,3 +39,11 @@ Each possible sum creates it's own equivalence class. So there are $7$ equivalen > $[5]_(~) = {(2, 3), (3, 2)}$ > $[6]_(~) = {(3, 3)}$ +## Binary Relation +A binary relation is a relation $R$ between _exactly two_ elements $a in R$ and $b in R$. An example for a binary relation is $a <= b$ +## Orders +An **Order** is a mathematical way to sort, rank or compare elements within a set, where some elements come "before" and "after" others. + +A _binary relation_ is called an order if it is... +- a *reflexive relation* +- a *antisymmetric relation*