Skip to main content
Ch. 9 - Differential Equations
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Non è quello che usi tu?Cambia libro di testo
Capitolo 9, Problema 9.4.15

11–16. Initial value problems Solve the following initial value problems.


y'(t) − 3y = 12, y(1) = 4

Guida verificata passo dopo passo
1
Identify the type of differential equation: This is a first-order linear differential equation of the form \(y'(t) + p(t)y = q(t)\), where \(p(t) = -3\) and \(q(t) = 12\).
Find the integrating factor \(\mu(t)\) using the formula \(\mu(t) = e^{\int p(t) \, dt}\). Here, calculate \(\mu(t) = e^{\int -3 \, dt}\).
Multiply both sides of the differential equation by the integrating factor \(\mu(t)\) to rewrite the left side as the derivative of a product: \(\frac{d}{dt}[\mu(t) y(t)] = \mu(t) q(t)\).
Integrate both sides with respect to \(t\) to find \(\mu(t) y(t) = \int \mu(t) q(t) \, dt + C\), where \(C\) is the constant of integration.
Use the initial condition \(y(1) = 4\) to solve for the constant \(C\), then solve for \(y(t)\) by dividing both sides by \(\mu(t)\).

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
2m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

First-Order Linear Differential Equations

These are differential equations of the form y' + p(t)y = q(t). They can be solved using an integrating factor, which simplifies the equation into an exact derivative, allowing integration to find the general solution.
Video consigliato:
07:39
Classifying Differential Equations

Integrating Factor Method

This method involves multiplying the differential equation by an integrating factor, typically e^(∫p(t)dt), to rewrite the left side as the derivative of a product. This facilitates direct integration to solve for y(t).
Video consigliato:
07:33
Euler's Method

Initial Value Problems (IVP)

An IVP specifies the value of the solution at a particular point, such as y(1) = 4. After finding the general solution, the initial condition is used to determine the unique constant, yielding a specific solution.
Video consigliato:
Percorso guidato
05:03
Initial Value Problems
Pratica correlata
Domanda del libro di testo

33–42. Solving initial value problems Solve the following initial value problems.

p'(x) = 2/(x² + x), p(1) = 0

48
views
Domanda del libro di testo

45–46. Harvesting problems Consider the harvesting problem in Example 6.

If r = 0.05 and H = 500, for what values of p₀ is the amount of the resource decreasing? For what value of p₀ is the amount of the resource constant? If p₀ = 9000, when does the resource vanish?

48
views
Domanda del libro di testo

39–42. Special equations A special class of first-order linear equations have the form a(t)y'(t)+a'(t)y(t)=f(t), where a and f are given functions of t. Notice that the left side of this equation can be written as the derivative of a product, so the equation has the form

a(t)y'(t) + a'(t)y(t) = d/dt (a(t)y(t)) = f(t). 

Therefore, the equation can be solved by integrating both sides with respect to t. Use this idea to solve the following initial value problems. 


(t² + 1)y′(t) + 2ty = 3t², y(2) = 8

48
views
Domanda del libro di testo

17–18. {Use of Tech} Designing logistic functions Use the method of Example 1 to find a logistic function that describes the following populations. Graph the population function.


The population increases from 50 to 60 in the first month and eventually levels off at 150.

64
views
Domanda del libro di testo

Stability of Euler's method Consider the initial value problem y′(t) = −ay, y(0) = 1 where a > 0; it has the exact solution y(t) = e⁻ᵃᵗ, which is a decreasing function.


a. Show that Euler's method applied to this problem with time step h can be written u₀ = 1, uₖ₊₁ = (1 − ah)uₖ for k = 0, 1, 2, ...


b. Show by substitution that uₖ = (1 − ah)ᵏ is a solution of the equations in part (a), for k = 0, 1, 2, ...

67
views
Domanda del libro di testo

Explain how to solve a separable differential equation of the form

g(t)y'(y) = h(t)

79
views