Skip to main content
Ch. 8 - Techniques of Integration
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077당신이 사용하는 게 아니라요?교과서 변경
8장, 문제 8.PE.44

Evaluate the integrals in Exercises 37–44.
∫ eᵗ √[tan²(eᵗ) + 1] dt

검증된 단계별 안내
1
Recognize that the integral is of the form \(\int e^{t} \sqrt{\tan^{2}(e^{t}) + 1} \, dt\). Notice that inside the square root, we have \(\tan^{2}(e^{t}) + 1\), which can be simplified using a trigonometric identity.
Recall the Pythagorean identity: \(1 + \tan^{2}(x) = \sec^{2}(x)\). Applying this, rewrite the integrand as \(e^{t} \sqrt{\sec^{2}(e^{t})}\).
Since \(\sqrt{\sec^{2}(e^{t})} = |\sec(e^{t})|\), and assuming the domain where \(\sec(e^{t})\) is positive, the integrand simplifies to \(e^{t} \sec(e^{t})\).
Use substitution to simplify the integral: let \(u = e^{t}\). Then, \(du = e^{t} dt\), which means \(du = e^{t} dt\) or equivalently \(e^{t} dt = du\). Substitute these into the integral to get \(\int \sec(u) \, du\).
Now, the integral reduces to \(\int \sec(u) \, du\), which is a standard integral. You can proceed by recalling the formula for \(\int \sec(u) \, du\) and then substitute back \(u = e^{t}\) to express the answer in terms of \(t\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
4m
도움이 되었나요?

주요 개념

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

Integration of Exponential Functions

Understanding how to integrate functions involving exponential terms like e^t is essential. This includes recognizing when substitution can simplify the integral, especially when the exponent appears inside another function.
추천 영상:
05:11
Integrals of General Exponential Functions

Trigonometric Identities

Familiarity with trigonometric identities, such as 1 + tan²(x) = sec²(x), helps simplify expressions under the integral. Applying these identities can transform complex radicals into more manageable forms.
추천 영상:
7:17
Verifying Trig Equations as Identities

Substitution Method in Integration

The substitution method involves changing variables to simplify the integral. Identifying an inner function whose derivative appears elsewhere in the integrand allows rewriting the integral in a simpler form for direct integration.
추천 영상:
07:33
Euler's Method