Seperation of variables in the 2 dimensional wave equation

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Homework Help Overview

The discussion revolves around solving the two-dimensional wave equation using the method of separation of variables. The equation is presented with specific boundary conditions and an initial condition involving a function g(x,y).

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to apply the separation of variables method but expresses uncertainty about the process and seeks well-explained steps. Some participants question the formatting issues that may affect clarity.

Discussion Status

The discussion includes attempts to clarify the problem setup and the method to be used. Participants are engaging with the original poster's concerns about formatting and understanding, but there is no explicit consensus on the approach yet.

Contextual Notes

There are indications of formatting challenges in the posts, which may hinder the communication of mathematical expressions and attempts. The original poster emphasizes the need for clear explanations due to their current confusion regarding the problem.

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[SOLVED] separation of variables in the 2 dimensional wave equation

I'd like to apologize right away for the terrible formatting. I was trying to make it pretty and easy to read but I guess I'm just not used the system yet and I had one problem after another. As you'll see at one point the formatting pretty much went out the window. I hope you can still figure out what I'm trying to say. Sorry!

Homework Statement


Solve the wave equation in 2 dimensions by separation of variables.
([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]t[tex]^{2}[/tex])=4(([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]x[tex]^{2}[/tex])+([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]y[tex]^{2}[/tex]))
a=[tex]\pi[/tex]/2 , b=[tex]\pi[/tex]
V(0,y,t)=V(a,y,t)=0
V(x,0,t)=V(x,b,t)=0
V(x,y,0)=0
([tex]\delta[/tex]V)/([tex]\delta[/tex]t)(x,y,0)=g(x,y)=([tex]\pi[/tex]/2-x)([tex]\pi[/tex]-y)
Show that
V(x,y,t)=Sigma(n=1,[tex]\infty[/tex])Sigma(m=1,[tex]\infty[/tex])(((sin(2sqrt(lambda sub(nm))t))/(nm*sqrt(lambda sub(nm)))*sin(2nx)sin(m)y)
where
lambda sub(nm)=4n^2+m^2

Homework Equations


All I know is it's going to be semi-related to the general solution of the wave equation:
([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]t[tex]^{2}[/tex])=(k^2)*([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]x[tex]^{2}[/tex])

The Attempt at a Solution


I know that k^2 is going to be equal to the 4. Other then that I'm lost. If possible, well explained steps would be best so I can figure out what I'm doing.

Thanks for your help!
 
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[SOLVED] separation of variables in the 2 dimensional wave equation

I'd like to apologize right away for the terrible formatting. I was trying to make it pretty and easy to read but I guess I'm just not used the system yet and I had one problem after another. As you'll see at one point the formatting pretty much went out the window. I hope you can still figure out what I'm trying to say. Sorry!

Homework Statement


Solve the wave equation in 2 dimensions by separation of variables.
([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]t[tex]^{2}[/tex])=4(([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]x[tex]^{2}[/tex])+([tex]\delta[/tex][tex]^{2}[/tex]u)/([tex]\delta[/tex]y[tex]^{2}[/tex]))
a=[tex]\pi[/tex]/2 , b=[tex]\pi[/tex]
V(0,y,t)=V(a,y,t)=0
V(x,0,t)=V(x,b,t)=0
V(x,y,0)=0
([tex]\delta[/tex]V)/([tex]\delta[/tex]t)(x,y,0)=g(x,y)=([tex]\pi[/tex]/2-x)([tex]\pi[/tex]-y)
Show that
V(x,y,t)=Sigma(n=1,[tex]\infty[/tex])Sigma(m=1,[tex]\infty[/tex])(((sin(2sqrt(lambda sub(nm))t))/(nm*sqrt(lambda sub(nm)))*sin(2nx)sin(m)y)
where
lambda sub(nm)=4n^2+m^2

I would have left the relevant equations and attempted solutions parts, but for some reason I can't get it to post with that and I didn't have very much to say in those anyway. If possible, well explained steps would be best because I'm kind of lost, and then I can figure out what I'm doing.

Thanks for your help!
 
Dang it, it was posting but it came up with an error. Um... I don't know how to delete this right off hand, but give me a minute I'll see if I can figure it out.
 
It doesn't seem I can delete. If an admin reads this please delete this and one of the other copies.
 
I'll set this one and one other to solved to try to remove the amount of people opening it.
 
Sorry for the copies.
 
Please delete this one, setting it to solved to try to help remove additional readers of the copy.
 

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