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Ch. 9 - First-Order Differential Equations
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Non è quello che usi tu?Cambia libro di testo
Capitolo 9, Problema 9.1.8

Integral Equations
In Exercises 7–12, write an equivalent first-order differential equation
and initial condition for y.


y = ∫₁ ͯ 1/t dt

Guida verificata passo dopo passo
1
Identify the given integral equation: \(y = \int_{1}^{x} \frac{1}{t} \, dt\).
Recall the Fundamental Theorem of Calculus, which states that if \(y = \int_{a}^{x} f(t) \, dt\), then \(\frac{dy}{dx} = f(x)\).
Apply the theorem to differentiate both sides with respect to \(x\): \(\frac{dy}{dx} = \frac{1}{x}\).
Write the equivalent first-order differential equation: \(\frac{dy}{dx} = \frac{1}{x}\).
Determine the initial condition by evaluating \(y\) at the lower limit of integration: since \(y = \int_{1}^{x} \frac{1}{t} \, dt\), then \(y(1) = 0\).

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