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Ch. 10 - Infinite Sequences and Series
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077당신이 사용하는 게 아니라요?교과서 변경
10장, 문제 10.2.98

Find the value of b for which
1 + eᵇ + e²ᵇ + e³ᵇ + ⋯ = 9.

검증된 단계별 안내
1
Recognize that the given series is an infinite geometric series of the form \(1 + e^{b} + e^{2b} + e^{3b} + \cdots\).
Recall the formula for the sum of an infinite geometric series \(S = \frac{a}{1 - r}\), where \(a\) is the first term and \(r\) is the common ratio, with the condition \(|r| < 1\) for convergence.
Identify the first term \(a = 1\) and the common ratio \(r = e^{b}\) in the series.
Set up the equation for the sum: \(\frac{1}{1 - e^{b}} = 9\).
Solve this equation for \(b\) by isolating \(e^{b}\) and then taking the natural logarithm to find \(b\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
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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 found by multiplying the previous term by a constant ratio. For example, the series 1 + r + r² + r³ + ⋯ converges if |r| < 1, and its sum can be calculated using a specific formula.
추천 영상:
가이드 코스
06:00
Geometric Series

Sum of an Infinite Geometric Series

If the common ratio r of a geometric series satisfies |r| < 1, the infinite sum converges to S = 1 / (1 - r). This formula allows us to find the sum of infinitely many terms without adding them individually.
추천 영상:
가이드 코스
06:00
Geometric Series

Solving Exponential Equations

Solving exponential equations involves isolating the variable in the exponent. This often requires applying logarithms or algebraic manipulation to rewrite the equation in a solvable form.
추천 영상:
5:47
Solving Exponential Equations Using Logs