tence or two what is wrong with the follo Let~ be a relation on a set S. If ~is reflexive. ~ is symmetric and transitive, and let with a a and b. Since ~ is symmetric, we h- is transitive, we have that a ~ a
tence or two what is wrong with the follo Let~ be a relation on a set S. If ~is reflexive. ~ is symmetric and transitive, and let with a a and b. Since ~ is symmetric, we h- is transitive, we have that a ~ a
Calculus: Early Transcendentals
8th Edition
ISBN:9781285741550
Author:James Stewart
Publisher:James Stewart
Chapter1: Functions And Models
Section: Chapter Questions
Problem 1RCC: (a) What is a function? What are its domain and range? (b) What is the graph of a function? (c) How...
Related questions
Question

Transcribed Image Text:**Question 7.** Explain in a sentence or two what is wrong with the following proof.
**Proposition.** Let \( \sim \) be a relation on a set \( S \). If \( \sim \) is symmetric and transitive, then \( \sim \) is reflexive.
**Proof.** Suppose \( \sim \) is symmetric and transitive, and let \( a \in S \). We will show that \( a \sim a \).
Suppose \( b \in S \) with \( a \sim b \). Since \( \sim \) is symmetric, we have that \( b \sim a \). Since \( a \sim b, b \sim a \) and \( \sim \) is transitive, we have that \( a \sim a \). \( \square \)
**Explanation of the Error:**
The proof incorrectly assumes the existence of an element \( b \) such that \( a \sim b \) without any justification. To prove reflexivity, \( a \sim a \) must be demonstrated for all elements \( a \in S \) unconditionally. The approach relies on an unwarranted assumption, thus invalidating the proof.
Expert Solution

This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps with 2 images

Recommended textbooks for you

Calculus: Early Transcendentals
Calculus
ISBN:
9781285741550
Author:
James Stewart
Publisher:
Cengage Learning

Thomas' Calculus (14th Edition)
Calculus
ISBN:
9780134438986
Author:
Joel R. Hass, Christopher E. Heil, Maurice D. Weir
Publisher:
PEARSON

Calculus: Early Transcendentals (3rd Edition)
Calculus
ISBN:
9780134763644
Author:
William L. Briggs, Lyle Cochran, Bernard Gillett, Eric Schulz
Publisher:
PEARSON

Calculus: Early Transcendentals
Calculus
ISBN:
9781285741550
Author:
James Stewart
Publisher:
Cengage Learning

Thomas' Calculus (14th Edition)
Calculus
ISBN:
9780134438986
Author:
Joel R. Hass, Christopher E. Heil, Maurice D. Weir
Publisher:
PEARSON

Calculus: Early Transcendentals (3rd Edition)
Calculus
ISBN:
9780134763644
Author:
William L. Briggs, Lyle Cochran, Bernard Gillett, Eric Schulz
Publisher:
PEARSON

Calculus: Early Transcendentals
Calculus
ISBN:
9781319050740
Author:
Jon Rogawski, Colin Adams, Robert Franzosa
Publisher:
W. H. Freeman


Calculus: Early Transcendental Functions
Calculus
ISBN:
9781337552516
Author:
Ron Larson, Bruce H. Edwards
Publisher:
Cengage Learning