Showing a general solution for a wave on a string fixed at one end

[catpants]

Homework Statement

http://img811.imageshack.us/img811/1989/problem1.png

Homework Equations

All shown in the above link, AFAIK

The Attempt at a Solution

Not worried about part a.
For part b, when they say "assume the string is initially at rest" I took that to mean:
\frac{\delta\Psi(x,0)}{\delta t}=0
But I don't know if that is right. It would be used as some sort of initial conditions for solving some diff eq. But I don't understand what that diff eq would be, or how to set it up. I would imagine I solve this diff eq using sep of vars?

 

[HallsofIvy]

The wave equation, which I presume you have already seen, since it is not mentioned in the problem is
\frac{\partial^2 \psi}{\partial x^2}= \frac{1}{c^2}\frac{\partial^2\psi}{\partial t^2}.

Yes, an initial condition is
\frac{\partial \psi(x, 0)}{\partial t}= 0[/math]<br /> <br /> (By the way, use &quot;\partial&quot; to get the \partial in LaTex.)

 

[catpants]

I think the wave equation is what I was missing. Do I try and solve it using separation of variables? Also, the end of your post got mangled, what were you trying to say?

Thanks!