From 15c3f2f85e34c2be008ba114b7d157da96176262 Mon Sep 17 00:00:00 2001
From: George Wilkinson <boris@Georges-MacBook-Pro.local>
Date: Fri, 31 Jan 2025 09:13:25 +0000
Subject: [PATCH] vault backup: 2025-01-31 09:13:25

---
 .obsidian/core-plugins.json                   |  3 +-
 .obsidian/workspace.json                      | 24 ++++--
 ...l - Introduction to Propositional Logic.md | 75 +++++++++++++++++++
 3 files changed, 96 insertions(+), 6 deletions(-)
 create mode 100644 AI & Data Mining/Week 20/Chapter 20 Tutorial - Introduction to Propositional Logic.md

diff --git a/.obsidian/core-plugins.json b/.obsidian/core-plugins.json
index 28cfcee..44712e7 100755
--- a/.obsidian/core-plugins.json
+++ b/.obsidian/core-plugins.json
@@ -26,5 +26,6 @@
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   "file-recovery": true,
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 }
\ No newline at end of file
diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json
index 4df63b5..8f5513d 100755
--- a/.obsidian/workspace.json
+++ b/.obsidian/workspace.json
@@ -20,8 +20,21 @@
               "icon": "lucide-file",
               "title": "Week 20 - Intro to Propositional Logic"
             }
+          },
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+            "id": "cc4f0e641615871b",
+            "type": "leaf",
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+              "type": "release-notes",
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+              },
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+              "title": "Release Notes 1.8.3"
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     "direction": "vertical"
@@ -67,7 +80,8 @@
             "state": {
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               "title": "Files"
@@ -198,10 +212,11 @@
       "mermaid-tools:Open Mermaid Toolbar": false
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-  "active": "87fc52db0e53c854",
+  "active": "cc4f0e641615871b",
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-    "AI & Data Mining/Week 20/Propositional Logic Examples.md",
+    "AI & Data Mining/Week 20/Chapter 20 Tutorial - Introduction to Propositional Logic.md",
     "AI & Data Mining/Week 20/Week 20 - Intro to Propositional Logic.md",
+    "AI & Data Mining/Week 20/Propositional Logic Examples.md",
     "Networking and Security/Week 20/hashcat-exercise/test-dict",
     "Networking and Security/Week 20/hashcat-exercise/view-sample-password.sh",
     "Networking and Security/Week 20/hashcat-exercise/crack-these-please-sha512",
@@ -245,7 +260,6 @@
     "Data Structures/AI Notes/ADT Linear List.md",
     "Data Structures/Focused Exam Revision.md",
     "Data Structures/GPT Answers to Past Paper/Question 3.md",
-    "Data Structures/GPT Answers to Past Paper/Question 2.md",
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diff --git a/AI & Data Mining/Week 20/Chapter 20 Tutorial - Introduction to Propositional Logic.md b/AI & Data Mining/Week 20/Chapter 20 Tutorial - Introduction to Propositional Logic.md
new file mode 100644
index 0000000..6c3dfe3
--- /dev/null
+++ b/AI & Data Mining/Week 20/Chapter 20 Tutorial - Introduction to Propositional Logic.md	
@@ -0,0 +1,75 @@
+1. Which of the following English sentences express a proposition?
+(a) I think therefore I am.
+Proposition
+
+(b) Do as I say, not as I do!
+Command
+
+(c) Whenever the assignment x = y is executed, the value of y remains unaltered.
+Proposition
+
+(d) Write clearly and legibly.
+Command
+
+(e) How do you know your answers are correct?
+Question
+
+1. List the atomic propositions and connectives which appear in the following propositions and write down a well-formed formula for each one.
+
+(a) If it rains then I am going to get wet.
+Atomic Propositions:
+	It rains
+	I am going to get wet
+Connectives:
+	If
+	Then
+Formula: p => q
+
+(b) Increased spending overheats the economy.
+Atomic Propositions:
+	Increased spending 
+	Overheats the economy
+Connectives: 
+	None, implied non-linguistic
+Formula: p => q
+
+(c) Increased spending coupled with tax cuts overheats the economy.
+Atomic Propositions:
+	Increased spending
+	There are tax cuts 
+	Overheated economy
+Connectives:
+	Coupled with
+Formula: p ^ q => r
+
+(d) Overheating economy is a synonym for rise in excess demand.
+Atomic Propositions:
+	Overheating economy
+	Rise in excess demand
+Connectives:
+	is a synonym for
+Formula: p <=> q
+
+(e) Inflation either rises or does not.
+Atomic Propositions:
+	Inflation rises
+	Inflation does not rise
+Connectives:
+	either / or
+Formula: p 
+
+1. Remove as many brackets as possible from the following propositions without altering their meaning (i.e. the truth table).
+
+(a) ((q ⇔((¬r) ∨(s ∧p))) ⇔(q ⇒p))
+(b) (((p ∧(¬q)) ∧r) ∨s)
+(c) ((p ⇒(q ∨r)) ∧(¬(r ⇒s)))
+(d) ((¬(¬(¬(q ∨r)))) ⇔(q ⇔r))
+(e) (p ∨(q ∨r))
+
+1. Decide using truth tables whether each of the following is a tautology, contradiction or contingency.
+
+(a) p ⇒¬p
+
+(b) p ∧q ⇒p
+
+(c) (p ⇒¬p) ∧(¬p ⇒p)