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**1. **Geometry Notes Section 2-2

**2. **What you’ll learn How to determine truth values of conjunctions and disjunctions
How to construct truth tables

**3. **Vocabulary Statement
Premise
Truth value
negation
Compound statement
Conjunction
Disjunction
Truth table

**4. **Determining Truth Values Statement—any sentence that is true or false
Usually denoted by p or q (the letter p or the letter q represents the whole statement)
Premise – just a simple statement
Truth Value—Two choices TRUE or FALSE

**5. **Negations Negation-the opposite of a statement
Notation-- ~p

**6. **Determining Truth Values One more example . . . .

**7. **Conjunctions A compound statement formed by joining two or more simple statements with the word AND.
Symbolically—
Let p represent a simple statement
Let q represent a second simple statement
The conjunction is written as p ? q
Read as “p and q”

**8. **Example Let p represent “It is Tuesday.”
Let q represent “There is school tomorrow.”
The conjunction is
It is Tuesday and there is school tomorrow.

**9. **Truth Value of Conjunctions-- A conjunction is only true when both simple statements are true.

**10. **disjunctions A compound statement formed by joining two or more simple statements with the word OR.
Symbolically—
Let p represent a simple statement
Let q represent a second simple statement
The disjunction is written as p ? q
Read as “p or q”

**11. **Example Let p represent “It is Tuesday.”
Let r represent “It is snowing.”
The disjunction is
It is Tuesday or it is snowing.

**12. **Truth Value of Disjunctions-- A disjunction is true when only one simple statement is true.

**13. **Conjunctions and Disjunctions can be illustrated by. . . . Venn Diagrams

**14. **Conjunctions and Disjunctions can be illustrated by. . . . Truth Tables
You can compute the truth value of a conjunction or disjunction using truth tables.
First consider all possible truth value combinations for p and q (You will want to set this up the same way each time).

**15. **Conjunctions—”AND”
Take it one row at a time

**17. **p ? q (only has to be true)

**19. **Have you learned? How to determine truth values of conjunctions and disjunctions?
How to construct truth tables?
Assignment: Worksheet 2.2