EDGE Math 8

NEGATIONS OF STATEMENTS

New statements can be formed from given statements. One possible way to do this is by negating a statement.

Definition

The negation of a statement p is formed by inserting the word "not" at a proper place in p.

The following table shows the relationship between a statement and its negation:

Truth Table of Negations of Statements

Example

State the negation of each statement and verify its truth value.

1.	An angle that measures 90° is a right angle.
2.	$2 + 3 < 5$

Solution

1.	The following is the negation of statement 1:

"An angle that measures 90° is not a right angle." It is false.

2.	The following is the negation of statement 2:

"2 + 3 is not less than 5" or

" 2 + 3 > 5. "

This negation is true.