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Ch. 7 - Transcendental Functions
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Not the one you use?Change textbook
Chapter 7, Problem 7.3.113

Evaluate the integrals in Exercises 111–114.
113. ∫₁^(1/x) (1 / t) dt,x > 0

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1
Identify the integral to be evaluated: \(\int_{1}^{\frac{1}{x}} \frac{1}{t} \, dt\) where \(x > 0\).
Recall the antiderivative of the integrand \(\frac{1}{t}\), which is \(\ln|t|\).
Apply the Fundamental Theorem of Calculus, which states that \(\int_{a}^{b} f(t) \, dt = F(b) - F(a)\), where \(F\) is an antiderivative of \(f\).
Substitute the limits of integration into the antiderivative: \(\ln\left| \frac{1}{x} \right| - \ln|1|\).
Simplify the expression using logarithm properties, such as \(\ln\left( \frac{1}{x} \right) = -\ln(x)\) and \(\ln(1) = 0\), to express the integral in terms of \(x\).

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Definite Integral and Variable Limits

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