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Ch. 3 - Derivatives
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 84b

The following limits represent f'(a) for some function f and some real number a.
b. Evaluate the limit by computing f'(a).
lim x🠂1 x¹⁰⁰-1 / x-1

검증된 단계별 안내
1
Step 1: Recognize that the given limit represents the derivative of a function at a point. Specifically, it is the definition of the derivative f'(a) at a = 1 for the function f(x) = x^{100}.
Step 2: Recall the definition of the derivative: f'(a) = \(\lim\)_{x \(\to\) a} \(\frac{f(x) - f(a)}{x - a}\). In this case, f(x) = x^{100} and a = 1, so f(1) = 1^{100} = 1.
Step 3: Substitute f(x) = x^{100} and f(1) = 1 into the derivative definition: \(\lim\)_{x \(\to\) 1} \(\frac{x^{100}\) - 1}{x - 1}.
Step 4: Notice that the expression \(\frac{x^{100}\) - 1}{x - 1} is an indeterminate form 0/0 as x approaches 1. To resolve this, apply L'Hôpital's Rule, which states that if \(\lim\)_{x \(\to\) c} \(\frac{f(x)}{g(x)}\) = \(\frac{0}{0}\), then \(\lim\)_{x \(\to\) c} \(\frac{f(x)}{g(x)}\) = \(\lim\)_{x \(\to\) c} \(\frac{f'(x)}{g'(x)}\).
Step 5: Differentiate the numerator and the denominator separately: f'(x) = 100x^{99} and g'(x) = 1. Then, apply L'Hôpital's Rule: \(\lim\)_{x \(\to\) 1} \(\frac{100x^{99}\)}{1}. Evaluate this limit by substituting x = 1.

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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.

Limits

A limit is a fundamental concept in calculus that describes the behavior of a function as its input approaches a certain value. It helps in understanding how functions behave near specific points, which is crucial for defining derivatives and integrals. In this context, evaluating the limit as x approaches 1 allows us to analyze the function's behavior at that point.
추천 영상:
05:50
One-Sided Limits

Derivatives

The derivative of a function at a point measures the rate at which the function's value changes as its input changes. It is defined as the limit of the average rate of change of the function over an interval as the interval approaches zero. In this question, f'(a) represents the derivative of the function f at the point a, which can be computed using the limit provided.
추천 영상:

L'Hôpital's Rule

L'Hôpital's Rule is a method for evaluating limits that result in indeterminate forms, such as 0/0 or ∞/∞. It states that if the limit of f(x)/g(x) leads to an indeterminate form, the limit can be found by taking the derivative of the numerator and the derivative of the denominator. This rule is particularly useful in the given limit problem, where direct substitution leads to an indeterminate form.
추천 영상:
5:50
Power Rules