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Ch. 5 - Integrals
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Not the one you use?Change textbook
Chapter 5, Problem 5.PE.35

Express the solutions of the initial value problems in Exercises 35 and 36 in terms of integrals.


dy/dx = sin x/x , y(5) = -3

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Identify the given differential equation and initial condition: \( \frac{dy}{dx} = \frac{\sin x}{x} \) with \( y(5) = -3 \).
Recognize that this is a first-order differential equation where \( \frac{dy}{dx} \) is given explicitly as a function of \( x \).
To find \( y(x) \), integrate both sides with respect to \( x \): \[ y(x) = \int \frac{\sin x}{x} \, dx + C \], where \( C \) is the constant of integration.
Use the initial condition \( y(5) = -3 \) to solve for \( C \): \[ -3 = \int_{}^{5} \frac{\sin t}{t} \, dt + C \]. Note that the variable of integration is changed to \( t \) to avoid confusion.
Express the solution explicitly in terms of an integral from 5 to \( x \): \[ y(x) = -3 + \int_5^{x} \frac{\sin t}{t} \, dt \]. This represents the solution in integral form.

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Key Concepts

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

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