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Ch. 1 - Functions
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243당신이 사용하는 게 아니라요?교과서 변경
1장, 문제 97

Identify the amplitude and period of the following functions.
g(θ)=3cos(θ3)g\(\left\)(\(\theta\]\right\))=3\(\cos\[\left\)(\(\frac{\theta}{3}\]\right\))

검증된 단계별 안내
1
The given function is g(θ) = 3cos(θ/3). This is a cosine function of the form a * cos(bθ), where a is the amplitude and b affects the period.
Identify the amplitude: In the function g(θ) = 3cos(θ/3), the coefficient of the cosine function is 3. Therefore, the amplitude is the absolute value of this coefficient, which is |3| = 3.
Determine the period: The period of a basic cosine function cos(θ) is 2π. For a function of the form cos(bθ), the period is adjusted by the factor b, and is given by the formula 2π/|b|.
In the function g(θ) = 3cos(θ/3), the value of b is 1/3 (since θ/3 can be rewritten as (1/3)θ). Therefore, the period is 2π divided by 1/3, which simplifies to 2π * 3.
Thus, the amplitude of the function is 3, and the period is 6π.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m
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주요 개념

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

Amplitude

Amplitude refers to the maximum value of a periodic function, specifically the height of the wave from its midline to its peak. In the function g(θ) = 3cos(θ/3), the amplitude is represented by the coefficient of the cosine function, which is 3. This means the function oscillates between 3 and -3.
추천 영상:
가이드 코스
3:40
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Period

The period of a periodic function is the length of one complete cycle of the wave. For the cosine function, the standard period is 2π. In the function g(θ) = 3cos(θ/3), the period is affected by the coefficient of θ inside the cosine. The period can be calculated using the formula 2π divided by the coefficient of θ, which in this case is 1/3, resulting in a period of 6π.
추천 영상:
가이드 코스
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Phase Shift

Phase shift refers to the horizontal shift of a periodic function along the x-axis. While the given function g(θ) = 3cos(θ/3) does not include a phase shift term, understanding this concept is essential for analyzing more complex functions. A phase shift occurs when the argument of the cosine function is adjusted by a constant, affecting where the wave starts on the x-axis.
추천 영상:
가이드 코스
5:25
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