First order linear non-homogeneous PDE

In summary: I don't know about any systematic ways, but just looking at it, if you could find a u such that ux = 2 and uy = 0 that would do it. And that's easy.I don't know about any systematic ways, but just looking at it, if you could find a u such that ux = 2 and uy = 0 that would do it. And that's easy. Then, I think u=2x will work as a particular solution.But really, can anyone suggest a more general/systematic way to solve it that would work also for more complicated first order linear PDEs? Thanks! :)In summary, the student is struggling to find a particular solution to a non-hom
  • #1
kingwinner
1,270
0

Homework Statement


Find the general solution to the PDE and solve the initial value problem:
y2 (ux) + x2 (uy) = 2 y2, initial condition u(x, y) = -2y on y3 = x3 - 2


2. Homework Equations /concepts
First order linear non-homogeneous PDEs


The Attempt at a Solution


I know that the general solution to the non-homogeneous PDE = a particular soltuion to it + the general solution to the assoicated homogenous PDE, so I first consider to assocatied homogeneous equation:
y2 (ux) + x2 (uy) = 0

The characteristic equation is dy/dx = x2/y2
And the solution to this ODE is y3 - x3 = C where C is an arbitrary constant.
So the general solution to the homogeneous equation is u = f(y3 - x3) where f is arbitrary differentiable function of one variable.
But then I am stuck. How can I find a particular solution to the original non-homogeneous PDE? Is there a systematic way to find one such solution?

Any help is appreciated! :)
 
Physics news on Phys.org
  • #2
Can someone please help? I am still stuck on this problem... :(
 
  • #3
kingwinner said:
Find the general solution to the PDE...
y2 (ux) + x2 (uy) = 2 y2
...

How can I find a particular solution to the original non-homogeneous PDE? Is there a systematic way to find one such solution?

Any help is appreciated! :)

I don't know about any systematic ways, but just looking at it, if you could find a u such that ux = 2 and uy = 0 that would do it. And that's easy.
 
  • #4
LCKurtz said:
I don't know about any systematic ways, but just looking at it, if you could find a u such that ux = 2 and uy = 0 that would do it. And that's easy.
Then, I think u=2x will work as a particular solution.

But really, can anyone suggest a more general/systematic way to solve it that would work also for more complicated first order linear PDEs?

Thanks!
 

1. What is a first order linear non-homogeneous PDE?

A first order linear non-homogeneous PDE (partial differential equation) is a type of differential equation that involves functions of multiple variables and their partial derivatives. It is considered to be linear if the dependent variable and its derivatives appear only in the first power, and non-homogeneous if the equation contains a function that is not equal to zero.

2. How is a first order linear non-homogeneous PDE solved?

The general solution to a first order linear non-homogeneous PDE can be found by using the method of characteristics, which involves transforming the PDE into a system of ordinary differential equations. Alternatively, it can also be solved using separation of variables or by finding an integrating factor.

3. What are some real-world applications of first order linear non-homogeneous PDEs?

First order linear non-homogeneous PDEs have a wide range of applications in various fields of science and engineering, including fluid dynamics, heat transfer, electromagnetism, and finance. They can be used to model and analyze various physical phenomena and make predictions about their behavior.

4. How do first order linear non-homogeneous PDEs differ from other types of PDEs?

Unlike higher order PDEs, first order linear non-homogeneous PDEs only involve the first derivatives of the dependent variable. They also have a general solution that can be expressed in terms of arbitrary functions, rather than a specific set of constants. Additionally, they can be solved using specific methods such as the method of characteristics.

5. What are some common techniques used to solve first order linear non-homogeneous PDEs?

In addition to the method of characteristics, other techniques commonly used to solve first order linear non-homogeneous PDEs include separation of variables, exact equations, and the use of integrating factors. These methods can be applied depending on the specific form and properties of the PDE in question.

Similar threads

  • Calculus and Beyond Homework Help
Replies
2
Views
175
  • Calculus and Beyond Homework Help
Replies
2
Views
1K
  • Calculus and Beyond Homework Help
Replies
3
Views
570
  • Calculus and Beyond Homework Help
Replies
12
Views
1K
  • Calculus and Beyond Homework Help
Replies
11
Views
1K
  • Calculus and Beyond Homework Help
Replies
2
Views
1K
  • Calculus and Beyond Homework Help
Replies
5
Views
2K
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
2
Views
320
  • Differential Equations
Replies
2
Views
2K
Back
Top