Is This the Correct Approach to Solving Laplace's Equation?

In summary, the conversation was about determining whether certain functions were solutions of Laplace's equation uxx + uyy = 0, with a specific example of x^3 + 3xy^2. The participants discussed the correct procedure for finding derivatives and concluded that while the final result was correct, the steps for finding the derivatives were incorrect. They also mentioned that the topic was difficult to understand and requested for any additional advice.
  • #1
tesla93
23
0

Homework Statement



Determine whether each of the following functions is a solution of Laplace’s
equation uxx + uyy = 0.

x^3 + 3xy^2

ux=3x^2

uxx=6x

uy=6xy^2

uyy=6x

6x+6x=12x and is therefore not a solution

Did I do that right? I'm just learning about this topic and it's a little hard to understand. Can anyone give any advice as to if I approached this correctly?

 
Physics news on Phys.org
  • #2
while your result is correct, your steps are not written down correctly.
 
  • #3
Your derivatives are wrong. The procedure is correct, but your partial derivatives are wrong.

You have: [tex]f(x,y)=x^3+3xy^2[/tex]
Then, the derivative with respect to x is:
[tex]f_x(x,y)=3x^2+3y^2[/tex]

Everything else is okey. The result you found is fine because when you take the second derivative with respect to x the term involving y vanishes.
 

Related to Is This the Correct Approach to Solving Laplace's Equation?

What is Laplace's Equation?

Laplace's Equation is a second-order partial differential equation that is used to describe the steady-state behavior of a physical system, such as heat flow or electric potential. It is named after the French mathematician Pierre-Simon Laplace.

What is the significance of Laplace's Equation?

Laplace's Equation is significant because it is a fundamental tool in the study of physical phenomena, particularly in the fields of physics and engineering. It allows scientists to model and predict the behavior of various systems, making it an essential tool for understanding the world around us.

How is Laplace's Equation solved?

Laplace's Equation can be solved using a variety of methods, including separation of variables, Fourier series, and numerical methods. The specific method used depends on the boundary conditions and the complexity of the problem.

What are the applications of Laplace's Equation?

Laplace's Equation has a wide range of applications in physics, engineering, and mathematics. It is commonly used to model heat transfer, fluid flow, electrostatics, and other physical phenomena. It is also used in image and signal processing, finance, and other fields.

What are some common challenges when working with Laplace's Equation?

Some common challenges when working with Laplace's Equation include determining appropriate boundary conditions, dealing with nonlinear or time-dependent systems, and solving the equation in complex geometries. It also requires a strong understanding of mathematical techniques and physical principles.

Similar threads

  • Calculus and Beyond Homework Help
Replies
2
Views
268
  • Calculus and Beyond Homework Help
Replies
5
Views
2K
  • Calculus and Beyond Homework Help
Replies
24
Views
2K
  • Calculus and Beyond Homework Help
Replies
1
Views
1K
  • Topology and Analysis
Replies
3
Views
2K
  • Calculus and Beyond Homework Help
Replies
2
Views
18K
  • Precalculus Mathematics Homework Help
Replies
7
Views
1K
  • Calculus and Beyond Homework Help
Replies
7
Views
1K
  • Calculus and Beyond Homework Help
Replies
8
Views
4K
  • Calculus and Beyond Homework Help
Replies
4
Views
2K
Back
Top