/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 68 True or false. Give an explanati... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

True or false. Give an explanation for your answer. \(-3 < x < 2\) could be the interval of convergence of \(\sum C_{n} x^{n}\)

Short Answer

Expert verified
True; the interval \(-3 < x < 2\) can be an interval of convergence for a power series.

Step by step solution

01

Understand Series Convergence

A power series \( \sum C_{n} x^{n} \) is given. Its interval of convergence refers to the range of \( x \) values for which the series converges.
02

Interval Characteristics

The interval of convergence can be open, closed, or half-open (either \((a,b), [a,b), (a,b], or [a,b])\). It includes all \( x \) values where the series converges.
03

Analyze Given Interval

The given interval is \(-3 < x < 2\), which is an open interval from \(-3\) to \(2\). This indicates the series converges within this range but excludes the endpoints \(-3\) and \(2\).
04

Determine Possibility Based on Theory

An interval \((-3, 2)\) could be a legitimate interval of convergence as power series can have open intervals of convergence. Typically, convergence at endpoints may vary; thus the series can converge within such an open interval.
05

Conclusion

The statement is true. Given that \(-3 < x < 2\) is an open interval, it is possible for a power series’ interval of convergence to be \((-3, 2)\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Power Series
A power series is an infinite series of the form \[ \sum_{n=0}^{\infty} C_{n} x^{n} \]where \(C_{n}\) are coefficients and \(x\) is the variable. Each term in the series has \(x\) raised to an increasing power, starting from zero. The power series is a powerful tool in mathematical analysis and appears frequently in calculus and differential equations.
  • The coefficients \(C_{n}\) can be any real numbers.
  • \(x\) is a variable that can take values in a particular range where the series converges.
  • The series represents a function within its interval of convergence.
Understanding where this series converges or diverges is key; this is determined by the interval of convergence. Working with power series allows mathematicians to approximate more complex functions or solve differential equations effectively.
Convergence
Convergence refers to whether a series like the power series settles into a particular value as more terms are added. Not all series will converge. A series that converges does so when its sum approaches a finite limit when infinitely many terms are added. For a power series \(\sum C_{n} x^{n}\), convergence can be found using techniques like the Ratio Test or the Root Test.
  • For the Ratio Test, examine \(\lim_{n \to \infty} \left| \frac{C_{n+1} x^{n+1}}{C_{n} x^{n}} \right| \).
  • If this limit is less than 1, the series converges.
  • The Root Test involves \(\lim_{n \to \infty} \sqrt[n]{|C_{n} x^{n}|}\).
The range of \(x\) values for which the series converges comprises the interval of convergence. This concept is crucial for determining how a power series behaves and whether it can be used to represent a function in a specific range.
Open Interval
An open interval is a set of numbers that includes all real numbers between two bounds but not the bounds themselves. Represented as \((a, b)\), this interval contains all \(x\) satisfying \(a < x < b\). In the context of power series, the interval of convergence can often be an open interval.
  • Open intervals are useful for understanding where a series converges while excluding endpoints.
  • This kind of interval implies different behavior if analyzed towards its endpoints.
  • Convergence at the endpoints needs to be tested separately, as it does not automatically result from the series converging within the open interval.
The example provided, \(-3 < x < 2\), represents an open interval. It's an excellent illustration of where a power series might converge: within the interval, but not necessarily at its endpoints \(-3\) and \(2\). Understanding the nature of open intervals helps in properly analyzing the behavior of series like \(\sum C_{n} x^{n}\).

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Study anywhere. Anytime. Across all devices.