The unit step function IR→ R is defined as if x < 0 { if x > 0. I(x) = 0 1 (i) Let s € (a, b), and suppose f : [a, b] → R is bounded on [a, b] and continu- ous at s. Let a(x) = I(x-s). Prove that f is Riemann-Stieltjes integrable with respect to a, and compute its integral.

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
100%

Could you teach me how to show (i)?

The unit step function \( I : \mathbb{R} \to \mathbb{R} \) is defined as

\[
I(x) = 
\begin{cases} 
0 & \text{if } x \leq 0 \\
1 & \text{if } x > 0 
\end{cases}
\]

(i) Let \( s \in (a, b) \), and suppose \( f : [a, b] \to \mathbb{R} \) is bounded on \([a, b]\) and continuous at \( s \). Let \( \alpha(x) = I(x-s) \). Prove that \( f \) is Riemann-Stieltjes integrable with respect to \(\alpha\), and compute its integral.

(ii) Let \( s_1, s_2, \ldots, s_n \) be distinct points in \((a, b)\), and suppose that \( f \) is continuous on \([a, b]\). Compute the Riemann-Stieltjes integral of \( f \) with respect to \(\alpha : \mathbb{R} \to \mathbb{R}\) defined as \(\alpha(x) = \sum_{i=1}^{n} I(x - s_i)\).
Transcribed Image Text:The unit step function \( I : \mathbb{R} \to \mathbb{R} \) is defined as \[ I(x) = \begin{cases} 0 & \text{if } x \leq 0 \\ 1 & \text{if } x > 0 \end{cases} \] (i) Let \( s \in (a, b) \), and suppose \( f : [a, b] \to \mathbb{R} \) is bounded on \([a, b]\) and continuous at \( s \). Let \( \alpha(x) = I(x-s) \). Prove that \( f \) is Riemann-Stieltjes integrable with respect to \(\alpha\), and compute its integral. (ii) Let \( s_1, s_2, \ldots, s_n \) be distinct points in \((a, b)\), and suppose that \( f \) is continuous on \([a, b]\). Compute the Riemann-Stieltjes integral of \( f \) with respect to \(\alpha : \mathbb{R} \to \mathbb{R}\) defined as \(\alpha(x) = \sum_{i=1}^{n} I(x - s_i)\).
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 5 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,