5. Let x and y be irrational numbers such that x-y is also irrational. Define sets A and B by A = {x +r:reQ} and B = {y+r:reQ). Prove that the sets A and B have no elements in common. be the set of all numbers of the form a t b/2 where a and b are arbitrary
5. Let x and y be irrational numbers such that x-y is also irrational. Define sets A and B by A = {x +r:reQ} and B = {y+r:reQ). Prove that the sets A and B have no elements in common. be the set of all numbers of the form a t b/2 where a and b are arbitrary
Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
Related questions
Question
![**5. Let \( x \) and \( y \) be irrational numbers such that \( x - y \) is also irrational. Define sets \( A \) and \( B \) by \( A = \{ x + r : r \in \mathbb{Q} \} \) and \( B = \{ y + r : r \in \mathbb{Q} \} \). Prove that the sets \( A \) and \( B \) have no elements in common.**
**Explanation:**
The problem involves showing that two sets constructed by adding rational numbers to given irrational numbers are disjoint, under the condition that the difference between the irrational numbers is also irrational. Here’s the detailed reasoning:
1. **Definitions of Sets:**
- Set \( A = \{ x + r : r \in \mathbb{Q} \} \): This represents all numbers formed by adding any rational number \( r \) to the irrational number \( x \).
- Set \( B = \{ y + r : r \in \mathbb{Q} \} \): This represents all numbers formed by adding any rational number \( r \) to the irrational number \( y \).
2. **Condition:**
- \( x - y \) is irrational.
3. **Proof Strategy:**
- Assume for contradiction that there exists some element common to both sets \( A \) and \( B \).
- Then there exist rational numbers \( r_1 \) and \( r_2 \) such that \( x + r_1 = y + r_2 \).
- Rearranging gives \( x - y = r_2 - r_1 \), which implies that \( x - y \) is rational, a contradiction.
Therefore, the sets \( A \) and \( B \) have no elements in common.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Fde096970-4fbf-4bcb-afca-efa41531f77d%2Fb0dc1131-9a4a-4466-936d-d4baf16f5cac%2Fe3lwpes_processed.jpeg&w=3840&q=75)
Transcribed Image Text:**5. Let \( x \) and \( y \) be irrational numbers such that \( x - y \) is also irrational. Define sets \( A \) and \( B \) by \( A = \{ x + r : r \in \mathbb{Q} \} \) and \( B = \{ y + r : r \in \mathbb{Q} \} \). Prove that the sets \( A \) and \( B \) have no elements in common.**
**Explanation:**
The problem involves showing that two sets constructed by adding rational numbers to given irrational numbers are disjoint, under the condition that the difference between the irrational numbers is also irrational. Here’s the detailed reasoning:
1. **Definitions of Sets:**
- Set \( A = \{ x + r : r \in \mathbb{Q} \} \): This represents all numbers formed by adding any rational number \( r \) to the irrational number \( x \).
- Set \( B = \{ y + r : r \in \mathbb{Q} \} \): This represents all numbers formed by adding any rational number \( r \) to the irrational number \( y \).
2. **Condition:**
- \( x - y \) is irrational.
3. **Proof Strategy:**
- Assume for contradiction that there exists some element common to both sets \( A \) and \( B \).
- Then there exist rational numbers \( r_1 \) and \( r_2 \) such that \( x + r_1 = y + r_2 \).
- Rearranging gives \( x - y = r_2 - r_1 \), which implies that \( x - y \) is rational, a contradiction.
Therefore, the sets \( A \) and \( B \) have no elements in common.
Expert Solution
![](/static/compass_v2/shared-icons/check-mark.png)
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 3 steps with 3 images
![Blurred answer](/static/compass_v2/solution-images/blurred-answer.jpg)
Similar questions
- Recommended textbooks for youAdvanced Engineering MathematicsAdvanced MathISBN:9780470458365Author:Erwin KreyszigPublisher:Wiley, John & Sons, IncorporatedNumerical Methods for EngineersAdvanced MathISBN:9780073397924Author:Steven C. Chapra Dr., Raymond P. CanalePublisher:McGraw-Hill EducationIntroductory Mathematics for Engineering Applicat…Advanced MathISBN:9781118141809Author:Nathan KlingbeilPublisher:WILEYAdvanced Engineering MathematicsAdvanced MathISBN:9780470458365Author:Erwin KreyszigPublisher:Wiley, John & Sons, IncorporatedNumerical Methods for EngineersAdvanced MathISBN:9780073397924Author:Steven C. Chapra Dr., Raymond P. CanalePublisher:McGraw-Hill EducationIntroductory Mathematics for Engineering Applicat…Advanced MathISBN:9781118141809Author:Nathan KlingbeilPublisher:WILEYMathematics For Machine TechnologyAdvanced MathISBN:9781337798310Author:Peterson, John.Publisher:Cengage Learning,