Attachment 25289

Basically, I have to use u = Real (f(x)e^-iwt) and sub it into the wave equation.

Simplify it etc,

then use say u= e^at to solve the characteristics equation.

However, I get stuck.

Can someone show me how to do it.

Thank you

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- October 19th 2012, 04:58 PMprincessmath1d wave eqution (help urgent)
Attachment 25289

Basically, I have to use u = Real (f(x)e^-iwt) and sub it into the wave equation.

Simplify it etc,

then use say u= e^at to solve the characteristics equation.

However, I get stuck.

Can someone show me how to do it.

Thank you - October 20th 2012, 04:55 AMTheEmptySetRe: 1d wave eqution (help urgent)
- October 20th 2012, 01:38 PMprincessmathRe: 1d wave eqution (help urgent)
Yeah, that what I did. Btw you forgot the A(x) next to f''e^-iwt

You can cancel e^-iwt etc.

But I'm stuck on how do I find f(x). - October 20th 2012, 01:50 PMprincessmathRe: 1d wave eqution (help urgent)
In short, I'm stuck on how do I solve the second order differential equation.

- October 20th 2012, 02:21 PMTheEmptySetRe: 1d wave eqution (help urgent)
- October 21st 2012, 03:02 AMprincessmathRe: 1d wave eqution (help urgent)
No, the question doesn't have any boundary conditions.

Just said to find the ode f(x). - October 21st 2012, 03:09 AMprincessmathRe: 1d wave eqution (help urgent)
How would you go about solving that pde?

See what I get is

A(x)F''(x) + A'(x)F'(x) + w^2/c^2 F(x) = 0

and then I try letting m = e^bx

then solving for the charateristic, but then I get confused :(