# Conjunctions and disjunctions

- Intro Lesson: a5:28
- Intro Lesson: b5:44
- Lesson: 1a2:55
- Lesson: 1b3:03
- Lesson: 1c2:02
- Lesson: 2a4:46
- Lesson: 2b2:20
- Lesson: 2c2:43
- Lesson: 2d2:18
- Lesson: 2e2:07
- Lesson: 2f2:24
- Lesson: 3a3:00
- Lesson: 3b3:57
- Lesson: 3c2:32
- Lesson: 4a3:44
- Lesson: 4b2:35
- Lesson: 4c3:09
- Lesson: 4d2:46
- Lesson: 4e3:29
- Lesson: 4f3:13
- Lesson: 5a5:19
- Lesson: 5b3:34
- Lesson: 5c4:32

### Conjunctions and disjunctions

#### Lessons

__Notes:__A **conjunction** is a compound statement that is made by combining two or more statements with the word
"*and*". If any of the statements is false, then the entire conjunction is false. If all statements are true, then the conjunction is true. We can replace the word "*and*" with the symbol ˄.

A **disjunction** is a compound statement that is made by combining two or more statements with the word "*or*". If any of the statements is true, then the entire disjunction is true. If all statements are false, then the disjunction is false. We can replace the word "*or*" with the symbol ˅.

- IntroductionConjunctions and Disjunctions Overview:a)Conjunctionsb)Disjunctions
- 1.
**Conjunctions**Determine the truth value of the following conjunctions:

a)A square is a 4-sided polygon and a rectangle is a 5-sided polygonb)$10+7\times 2=72$ and $10\times 7+2=72$c)March is the third month of the year and December is the last month of the year - 2.The symbols represent the following statements:
$p$: A year has 52 weeks

Find the truth value of the following:

$q$: December is a summer month

$r$: A kilogram is 1000 gramsa)$p$ ˄ $q$b)$p$ ˄ $r$c)$p$ ˄ ~$q$d)~$r$ ˄ ~$p$e)$p$ ˄ ~$q$ ˄ $r$f)~$p$ ˄ $q$ ˄ ~$r$ - 3.
**Disjunctions**Determine the truth value of the following disjunctions:

a)1 metre is 100 centimetres or 1 metre is 10 centimetres.b)A right triangle always has an angle that is 90° degrees or the angles of a square are always 90° degrees.c)Breakfast is a meal or all meals are breakfasts. - 4.The symbols represent the following statements:
$p$: A week has 5 days

Find the truth value of the following:

$q$: A day has 24 hours

$r$: An hour has 60 secondsa)$p$ ˅ $q$b)$p$ ˅ $r$c)$p$ ˅ ~$q$d)~$r$ ˅ ~$p$e)~$p$ ˅ $q$ ˅ ~$r$f)$p$ ˅ ~$q$ ˅ ~$r$ - 5.
**Advanced Questions on Conjunctions and Disjunctions**Let $p$ and $q$ be statement. Fill in the blanks:

a)If $p$ is false, then $p$ ˄ $q$ is _______________.b)If $p$ is true, then $p$ ˅ $q$ is _______________.c)If ~$p$ is true, then $p$ ˄ $q$ is _______________.