Advanced Engineering Mathematics
Advanced Engineering Mathematics
10th Edition
ISBN: 9780470458365
Author: Erwin Kreyszig
Publisher: Wiley, John & Sons, Incorporated
Bartleby Related Questions Icon

Related questions

bartleby

Concept explainers

Topic Video
Question

 

 

### Proposition Analysis

**Problem:**
Examine the provided "proof" of the given "proposition." Is this "proposition" true? If not, identify a counterexample.

#### Proposition
Consider sets \( A \), \( B \), and \( C \) such that \( A \subseteq B \cup C \). This implies \( A \subseteq B \) or \( A \subseteq C \).

#### Provided Proof
To prove or disprove the proposition, follow these steps:

1. **Assumption:**
   Let \( x \) be any arbitrary object and suppose \( x \in A \).
   
2. **Implication:**
   Since \( A \subseteq B \cup C \), it implies \( x \in B \cup C \).
   
3. **Definition of Union:**
   By the definition of the union, \( x \in B \) or \( x \in C \).

4. **Conclusion:**
   Therefore, for any object \( x \), if \( x \in A \), then \( x \in B \) or \( x \in C \).

5. **Subset Definition:**
   Hence, by the definition of a subset, we can conclude \( A \subseteq B \) or \( A \subseteq C \).

#### Analysis and Error Identification

The provided "proof" contains a flaw. It incorrectly assumes that if \( x \) belongs to the union \( B \cup C \), then \( x \) necessarily belongs to either \( B \) or \( C \) independently for all elements in \( A \). However, there could be elements of \( A \) that belong to \( B \cup C \) but not entirely to one set \( B \) or \( C \).

#### Counterexample

Consider the following sets:
- \( A = \{1, 2\} \)
- \( B = \{1\} \)
- \( C = \{2\} \)

Here, \( A \subseteq B \cup C \) because every element of \( A \) is in the union of \( B \) and \( C \):
\[ A = \{1, 2\} \text{ and } B \cup C = \{1, 2\} \]

However, \( A \) is not a subset of \( B \) (since \(
expand button
Transcribed Image Text:### Proposition Analysis **Problem:** Examine the provided "proof" of the given "proposition." Is this "proposition" true? If not, identify a counterexample. #### Proposition Consider sets \( A \), \( B \), and \( C \) such that \( A \subseteq B \cup C \). This implies \( A \subseteq B \) or \( A \subseteq C \). #### Provided Proof To prove or disprove the proposition, follow these steps: 1. **Assumption:** Let \( x \) be any arbitrary object and suppose \( x \in A \). 2. **Implication:** Since \( A \subseteq B \cup C \), it implies \( x \in B \cup C \). 3. **Definition of Union:** By the definition of the union, \( x \in B \) or \( x \in C \). 4. **Conclusion:** Therefore, for any object \( x \), if \( x \in A \), then \( x \in B \) or \( x \in C \). 5. **Subset Definition:** Hence, by the definition of a subset, we can conclude \( A \subseteq B \) or \( A \subseteq C \). #### Analysis and Error Identification The provided "proof" contains a flaw. It incorrectly assumes that if \( x \) belongs to the union \( B \cup C \), then \( x \) necessarily belongs to either \( B \) or \( C \) independently for all elements in \( A \). However, there could be elements of \( A \) that belong to \( B \cup C \) but not entirely to one set \( B \) or \( C \). #### Counterexample Consider the following sets: - \( A = \{1, 2\} \) - \( B = \{1\} \) - \( C = \{2\} \) Here, \( A \subseteq B \cup C \) because every element of \( A \) is in the union of \( B \) and \( C \): \[ A = \{1, 2\} \text{ and } B \cup C = \{1, 2\} \] However, \( A \) is not a subset of \( B \) (since \(
Expert Solution
Check Mark
Knowledge Booster
Background pattern image
Advanced Math
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, advanced-math and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Text book image
Advanced Engineering Mathematics
Advanced Math
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Wiley, John & Sons, Incorporated
Text book image
Numerical Methods for Engineers
Advanced Math
ISBN:9780073397924
Author:Steven C. Chapra Dr., Raymond P. Canale
Publisher:McGraw-Hill Education
Text book image
Introductory Mathematics for Engineering Applicat...
Advanced Math
ISBN:9781118141809
Author:Nathan Klingbeil
Publisher:WILEY
Text book image
Mathematics For Machine Technology
Advanced Math
ISBN:9781337798310
Author:Peterson, John.
Publisher:Cengage Learning,
Text book image
Basic Technical Mathematics
Advanced Math
ISBN:9780134437705
Author:Washington
Publisher:PEARSON
Text book image
Topology
Advanced Math
ISBN:9780134689517
Author:Munkres, James R.
Publisher:Pearson,