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Ch. 8 - Techniques of Integration
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077당신이 사용하는 게 아니라요?교과서 변경
8장, 문제 8.8.4

The integrals in Exercises 1–34 converge. Evaluate the integrals without using tables.
∫₀⁴ dx / √(4 − x)

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1
Identify the integral to be solved: \(\int_0^4 \frac{dx}{\sqrt{4 - x}}\).
Recognize that the integrand involves a square root of a linear function, suggesting a substitution to simplify the integral.
Use the substitution \(u = 4 - x\), which implies \(du = -dx\) or \(dx = -du\). Also, change the limits of integration accordingly: when \(x=0\), \(u=4\); when \(x=4\), \(u=0\).
Rewrite the integral in terms of \(u\): \(\int_{u=4}^{u=0} \frac{-du}{\sqrt{u}} = \int_0^4 \frac{du}{\sqrt{u}}\) after reversing the limits to keep the integral positive.
Evaluate the integral \(\int_0^4 u^{-1/2} du\) by applying the power rule for integration: \(\int u^n du = \frac{u^{n+1}}{n+1} + C\) for \(n \neq -1\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
4m
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주요 개념

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

Improper Integrals and Convergence

An integral is improper if the interval of integration is infinite or the integrand becomes unbounded within the interval. Understanding convergence means determining whether the integral approaches a finite value. In this problem, the integrand has a singularity at x = 4, so recognizing the integral as improper is essential.
추천 영상:
가이드 코스
11:11
Improper Integrals: Infinite Intervals

Substitution Method for Integration

The substitution method simplifies integrals by changing variables to transform the integrand into a more manageable form. For example, setting a new variable equal to the expression inside the square root can help rewrite the integral in terms of a simpler function, making it easier to evaluate.
추천 영상:
07:33
Euler's Method

Evaluating Definite Integrals with Square Root Functions

Integrals involving square roots often require algebraic manipulation or trigonometric substitution to evaluate. Recognizing the form √(a - x) allows the use of substitution or standard integral formulas to find antiderivatives and then apply the limits to compute the definite integral.
추천 영상:
가이드 코스
05:43
Definition of the Definite Integral