Definition of Counter Example
Counterexample is an example that is used to disprove a statement.
Example of Counter Example
The opposite of a number is always positive.
Counterexample for the above statement: The opposite of 2 is - 2, a negative number.
Video Examples: Geometry - Inductive Reasoning & Counterexamples
Solved Example on Counter Example
Ques: Which of the following is a counterexample of the statement, "The perimeter of a rectangle can never be an odd number"?
A. Length of a rectangle is 3.25 in. and width is 5.25 in.
B. Length of a rectangle is 10 in. and width is 7 in.
C. Length of a rectangle is 6.5 in. and width is 4.5 in.
D. Length of a rectangle is 9 in. and width is 5 in.
Correct Answer: A
Step 1: The counterexample that disproves the given statement is:
'Length of a rectangle is 3.25 in. and width is 5.25 in.'