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Ch. 2 - Limits and Continuity
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077당신이 사용하는 게 아니라요?교과서 변경
2장, 문제 2.5.69

Use the Intermediate Value Theorem in Exercises 69–74 to prove that each equation has a solution. Then use a graphing calculator or computer grapher to solve the equations.
x³ − 3x − 1 = 0

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1
Identify the function f(x) = x³ − 3x − 1 and note that it is a polynomial, which is continuous everywhere.
Choose an interval [a, b] where the function changes sign, indicating a root exists. For example, test f(0) and f(2).
Calculate f(0) = 0³ − 3(0) − 1 = -1 and f(2) = 2³ − 3(2) − 1 = 3. Since f(0) < 0 and f(2) > 0, there is a sign change.
Apply the Intermediate Value Theorem: Since f(x) is continuous on [0, 2] and f(0) < 0 < f(2), there exists at least one c in (0, 2) such that f(c) = 0.
Use a graphing calculator or computer grapher to approximate the root of the equation x³ − 3x − 1 = 0 within the interval [0, 2].

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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.

Intermediate Value Theorem

The Intermediate Value Theorem states that if a continuous function f(x) takes on values f(a) and f(b) at two points a and b, and if f(a) and f(b) have opposite signs, then there exists at least one c in the interval (a, b) such that f(c) = 0. This theorem is crucial for proving the existence of a solution to the equation x³ − 3x − 1 = 0.
추천 영상:
06:11
Fundamental Theorem of Calculus Part 1

Continuous Functions

A function is continuous if there are no breaks, jumps, or holes in its graph over its domain. For the Intermediate Value Theorem to apply, the function x³ − 3x − 1 must be continuous over the interval being considered. Polynomial functions, like this one, are continuous everywhere, which allows us to use the theorem effectively.
추천 영상:
05:34
Intro to Continuity

Graphical Analysis

Graphical analysis involves using a graphing calculator or computer software to visualize the function and identify where it crosses the x-axis, indicating a root. By graphing x³ − 3x − 1, we can visually confirm the existence of a solution and approximate its value, complementing the theoretical proof provided by the Intermediate Value Theorem.
추천 영상:
05:02
Determining Differentiability Graphically