Exercise 4.6 Let m be Lebesgue measure. Suppose for each n, An is a Lebesgue measurable subset of [0, 1]. Let B consist of those points x that are in infinitely many of the An. (1) Show B is Lebesgue measurable. (2) If m(An) > 8 > 0 for each n, show m(B) > 8. (3) If E1 m(An) < o, prove that m(B) = 0. (4) Give an example where , m(An) = ∞, but m(B) = 0. n=1

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

I need help with Lebesgue measures for real analysis please, Thankyou for your help and time.

**Exercise 4.6**

Let \( m \) be Lebesgue measure. Suppose for each \( n \), \( A_n \) is a Lebesgue measurable subset of \([0, 1]\). Let \( B \) consist of those points \( x \) that are in infinitely many of the \( A_n \).

1. Show \( B \) is Lebesgue measurable.
2. If \( m(A_n) > \delta > 0 \) for each \( n \), show \( m(B) \geq \delta \).
3. If \( \sum_{n=1}^{\infty} m(A_n) < \infty \), prove that \( m(B) = 0 \).
4. Give an example where \( \sum_{n=1}^{\infty} m(A_n) = \infty \), but \( m(B) = 0 \).
Transcribed Image Text:**Exercise 4.6** Let \( m \) be Lebesgue measure. Suppose for each \( n \), \( A_n \) is a Lebesgue measurable subset of \([0, 1]\). Let \( B \) consist of those points \( x \) that are in infinitely many of the \( A_n \). 1. Show \( B \) is Lebesgue measurable. 2. If \( m(A_n) > \delta > 0 \) for each \( n \), show \( m(B) \geq \delta \). 3. If \( \sum_{n=1}^{\infty} m(A_n) < \infty \), prove that \( m(B) = 0 \). 4. Give an example where \( \sum_{n=1}^{\infty} m(A_n) = \infty \), but \( m(B) = 0 \).
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 4 steps

Blurred answer
Similar questions
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,