EXERCISE 2.1. Suppose (an) and (bn) are sequences of complex numbers, and the series Σo anz" and Σobn" have radii of convergence R₁ and R₂, respectively. Show that the radius of convergence R of the Cauchy product of these two series satisfies R≥ min{R₁, R₂}. Give an example of two series where strict inequality holds, R > min{R₁, R₂}. (Hints: Try using Mertens' Theorem for the first part; don't overthink the last part.)
EXERCISE 2.1. Suppose (an) and (bn) are sequences of complex numbers, and the series Σo anz" and Σobn" have radii of convergence R₁ and R₂, respectively. Show that the radius of convergence R of the Cauchy product of these two series satisfies R≥ min{R₁, R₂}. Give an example of two series where strict inequality holds, R > min{R₁, R₂}. (Hints: Try using Mertens' Theorem for the first part; don't overthink the last part.)
Algebra & Trigonometry with Analytic Geometry
13th Edition
ISBN:9781133382119
Author:Swokowski
Publisher:Swokowski
Chapter10: Sequences, Series, And Probability
Section10.2: Arithmetic Sequences
Problem 68E
Related questions
Question
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 4 steps
Recommended textbooks for you
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:
9781133382119
Author:
Swokowski
Publisher:
Cengage
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:
9781133382119
Author:
Swokowski
Publisher:
Cengage