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Ch. 11 - Power Series
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243당신이 사용하는 게 아니라요?교과서 변경
11장, 문제 11.2.67

Series to functions Find the function represented by the following series, and find the interval of convergence of the series. (Not all these series are power series.)


∑ₖ₌₀∞(√x − 2)ᵏ

검증된 단계별 안내
1
Recognize that the given series is a geometric series of the form \(\sum_{k=0}^\infty r^k\), where the common ratio \(r\) is \(\sqrt{x} - 2\).
Recall that a geometric series \(\sum_{k=0}^\infty r^k\) converges to the function \(\frac{1}{1-r}\) when \(|r| < 1\).
Write the function represented by the series as \(f(x) = \frac{1}{1 - (\sqrt{x} - 2)}\).
Simplify the denominator to get \(f(x) = \frac{1}{1 - \sqrt{x} + 2} = \frac{1}{3 - \sqrt{x}}\).
Determine the interval of convergence by solving the inequality \(|\sqrt{x} - 2| < 1\). This involves considering the values of \(x\) for which the absolute value condition holds, and also ensuring \(x \geq 0\) since \(\sqrt{x}\) is defined for non-negative \(x\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m
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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Geometric Series

A geometric series is a sum of terms where each term is a constant multiple (common ratio) of the previous one. It converges to a finite value if the absolute value of the ratio is less than 1, and its sum is given by S = a / (1 - r), where a is the first term and r is the ratio.
추천 영상:
가이드 코스
06:00
Geometric Series

Interval of Convergence

The interval of convergence is the set of all x-values for which a given series converges. For power or related series, it is found by applying convergence tests, often involving inequalities on the variable to ensure the series terms approach zero.
추천 영상:
08:44
Interval of Convergence

Manipulating Series with Functions

To find the function represented by a series, one must recognize the pattern of terms and rewrite the series in a closed form. This often involves identifying the series type and substituting expressions (like √x − 2) as the variable to simplify and find the sum function.
추천 영상:
가이드 코스
06:00
Geometric Series