Re: Solve[wave equation,bound.cond.]

*To*: mathgroup at smc.vnet.net*Subject*: [mg21545] Re: Solve[wave equation,bound.cond.]*From*: Paul Abbott <paul at physics.uwa.edu.au>*Date*: Fri, 14 Jan 2000 02:44:05 -0500 (EST)*Organization*: University of Western Australia*References*: <85i0ed$1od@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Karkaletsis Angelos wrote: > I am trying to get the analytical solution of > du/dt+c*du/dx=0,u[0,t]=a,u[x,0]=b, a,b real, but i can't.Does anybody > know? Dropping the boundary conditions, you can determine the general solution: In[1]:= u[x_, t_] = u[x, t] /. First[DSolve[D[u[x, t], x] + c*D[u[x, t], t] == 0, u[x, t], {x, t}]] Out[1]= C[1][t - c*x] C[1] is an arbitrary function. Supplying the boundary conditions you should be able to work out what is going on: In[2]:= {u[0, t] == a, u[x, 0] == b} Out[2]= {C[1][t] == a, C[1][-c*x] == b} Cheers, Paul