EDGE Math 8

DISJUNCTIONS OF STATEMENTS

The disjunction of statements p and q is "p or q." The word "or" is used in the sense of "either p or q, or both."

Definition

A disjunction consists of two or more statements connected by the word "or."

The truth table of disjunctions of statements is shown below.

Truth Table of Disjunctions of Statements

Example

Determine the truth value of each disjunction

1.	8 is even or 7 is odd.
2.	Angle B, which measures 53°, is an acute angle and $∠ C,$ which measures 89°, is an obtuse angle.

Solution

1.	The statement "8 is even" is true and the statement "7 is odd" is also true. Thus, the truth value of their disjunction is true.

2.	The statement "Angle B, which measures 53°, is an acute angle" is true and the statement " which measures 89°, is an obtuse angle" is false. Thus, the truth value of their disjunction is true.