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Ch. 7 - Transcendental Functions
Hass - Thomas' Calculus 15th Edition
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7장, 문제 7.8.5a

5. Which of the following functions grow faster than ln(x) as x→∞? Which grow at the same rate as ln(x)? Which grow slower?
a. log_3(x)

검증된 단계별 안내
1
Recall that logarithms with different bases differ only by a constant multiple. Specifically, for any base \(a > 0, a \neq 1\), \(\log_a(x) = \frac{\ln(x)}{\ln(a)}\).
Since \(\log_3(x) = \frac{\ln(x)}{\ln(3)}\), it is exactly \(\ln(x)\) multiplied by a positive constant \(\frac{1}{\ln(3)}\).
When comparing growth rates as \(x \to \infty\), multiplying by a positive constant does not change the rate of growth, so \(\log_3(x)\) and \(\ln(x)\) grow at the same rate.
Therefore, \(\log_3(x)\) neither grows faster nor slower than \(\ln(x)\); they grow at the same rate asymptotically.
In summary, \(\log_3(x)\) grows at the same rate as \(\ln(x)\) as \(x \to \infty\).

비슷한 문제에 대한 검증된 영상 답변:

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

주요 개념

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

Growth Rates of Logarithmic Functions

Logarithmic functions with different bases differ only by a constant factor. For example, log base 3 of x can be expressed as ln(x) divided by ln(3). This means all logarithmic functions grow at the same rate asymptotically, differing only by a constant multiplier.
추천 영상:
가이드 코스
04:16
Intro To Related Rates

Asymptotic Behavior and Limits

As x approaches infinity, comparing growth rates involves analyzing limits of ratios of functions. If the limit of f(x)/g(x) is a positive finite constant, f and g grow at the same rate. If the limit is zero or infinity, one grows slower or faster respectively.
추천 영상:
가이드 코스
5:50
Asymptotes of Hyperbolas

Big-O and Little-o Notation

Big-O and little-o notation describe relative growth rates of functions. If f(x) = O(g(x)), f grows no faster than g asymptotically. If f(x) = o(g(x)), f grows strictly slower than g. These notations help classify functions like logarithms, polynomials, and exponentials by their growth.
추천 영상:
11:35
Example 6: Shortest Rope