Use any method to evaluate the integrals in Exercises 15–38. Most will require trigonometric substitutions, but some can be evaluated by other methods.
∫ √(9 - w²) dw / w²

검증된 단계별 안내

Identify the integral to solve: \(\int \frac{\sqrt{9 - w^{2}}}{w^{2}} \, dw\).

Recognize that the integrand contains a square root of the form \(\sqrt{a^{2} - w^{2}}\), which suggests using a trigonometric substitution: let \(w = 3 \sin(\theta)\), where \(a = 3\).

Compute the differential: \(dw = 3 \cos(\theta) \, d\theta\). Also, rewrite the expressions inside the integral in terms of \(\theta\): \(\sqrt{9 - w^{2}} = \sqrt{9 - 9 \sin^{2}(\theta)} = 3 \cos(\theta)\) and \(w^{2} = 9 \sin^{2}(\theta)\).

Substitute all parts into the integral to express it entirely in terms of \(\theta\): replace \(\sqrt{9 - w^{2}}\) with \(3 \cos(\theta)\), \(w^{2}\) with \(9 \sin^{2}(\theta)\), and \(dw\) with \(3 \cos(\theta) \, d\theta\). This will simplify the integral to a trigonometric integral.

Simplify the resulting integral and use trigonometric identities to integrate with respect to \(\theta\). After integrating, substitute back \(\theta = \arcsin(\frac{w}{3})\) to express the answer in terms of \(w\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

도움이 되었나요?

주요 개념

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

Trigonometric Substitution

Trigonometric substitution is a technique used to evaluate integrals involving expressions like √(a² - x²), √(a² + x²), or √(x² - a²). By substituting x with a trigonometric function (e.g., x = a sin θ), the integral simplifies using trigonometric identities, making it easier to solve.

Integration of Rational Functions

Integration of rational functions involves integrating expressions where the integrand is a ratio of polynomials or functions. Recognizing when to simplify or rewrite the integrand, such as separating terms or using substitution, is essential for solving integrals involving algebraic expressions.

Use of Pythagorean Identities

Pythagorean identities like sin²θ + cos²θ = 1 are fundamental in trigonometric substitution. They allow the conversion of square root expressions into simpler trigonometric forms, facilitating the integration process by reducing complex radicals to manageable trigonometric expressions.

Use any method to evaluate the integrals in Exercises 15–38. Most will require trigonometric substitutions, but some can be evaluated by other methods.∫ √(9 - w²) dw / w²