O Show that if Si and S2 are convex sets in R™X", then so is t mxn S = {(x, y1 + y2) | x € R", y1, y2 € R", (x, y1) e

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question

It should be Rm+n instead of Rmxn

## Convex Sets and Their Partial Sums

### Problem 2.16

**Objective:**  
Show that if \( S_1 \) and \( S_2 \) are convex sets in \( \mathbb{R}^{m \times n} \), then their partial sum is also convex.

**Partial Sum Defined as:**  
\[ S = \{ (x, y_1 + y_2) \mid x \in \mathbb{R}^m, y_1, y_2 \in \mathbb{R}^n, (x, y_1) \in S_1, (x, y_2) \in S_2 \} \]

### Explanation

1. **Understanding Convex Sets:**
   - A set \( C \) in a real vector space is convex if, for any two points \( a \) and \( b \) in \( C \), the line segment joining \( a \) and \( b \) is also in \( C \).
   - Mathematically expressed, if \( \lambda \in [0, 1] \), then \( \lambda a + (1 - \lambda) b \in C \).

2. **Given Conditions:**
   - \( S_1 \) and \( S_2 \) are convex sets in \( \mathbb{R}^{m \times n} \).

3. **Challenge:**
   - Prove that the set \( S \) formed by the described operation is also convex.

4. **Approach to Solution:**
   - Verify if any linear combination of elements from \( S \) remains in \( S \).
   - Consider arbitrary elements \( a = (x, y_1 + y_2) \) and \( b = (x', y_1' + y_2') \) in \( S \).
   - Show that for any \( \lambda \in [0, 1] \), the combination \( \lambda a + (1 - \lambda) b \) is also in \( S \).

### Conclusion

By following these steps and verifying the properties, the convexity of the set \( S \) as defined can be confirmed. This demonstrates how the operation on two convex sets can lead to another convex set, maintaining the property of convexity.
Transcribed Image Text:## Convex Sets and Their Partial Sums ### Problem 2.16 **Objective:** Show that if \( S_1 \) and \( S_2 \) are convex sets in \( \mathbb{R}^{m \times n} \), then their partial sum is also convex. **Partial Sum Defined as:** \[ S = \{ (x, y_1 + y_2) \mid x \in \mathbb{R}^m, y_1, y_2 \in \mathbb{R}^n, (x, y_1) \in S_1, (x, y_2) \in S_2 \} \] ### Explanation 1. **Understanding Convex Sets:** - A set \( C \) in a real vector space is convex if, for any two points \( a \) and \( b \) in \( C \), the line segment joining \( a \) and \( b \) is also in \( C \). - Mathematically expressed, if \( \lambda \in [0, 1] \), then \( \lambda a + (1 - \lambda) b \in C \). 2. **Given Conditions:** - \( S_1 \) and \( S_2 \) are convex sets in \( \mathbb{R}^{m \times n} \). 3. **Challenge:** - Prove that the set \( S \) formed by the described operation is also convex. 4. **Approach to Solution:** - Verify if any linear combination of elements from \( S \) remains in \( S \). - Consider arbitrary elements \( a = (x, y_1 + y_2) \) and \( b = (x', y_1' + y_2') \) in \( S \). - Show that for any \( \lambda \in [0, 1] \), the combination \( \lambda a + (1 - \lambda) b \) is also in \( S \). ### Conclusion By following these steps and verifying the properties, the convexity of the set \( S \) as defined can be confirmed. This demonstrates how the operation on two convex sets can lead to another convex set, maintaining the property of convexity.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps

Blurred answer
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,