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NDSolve problem


I am trying to solve the following equation:

NDSolve[
        {D[v[b,y],b,b] - (.1 b - .3) D[v[b,y],b] ==  .1 v[b,y] ,
v[2,y]==-2,
        Derivative[1,0][v][25,y] == 0,v[25,y]==0}, v, {b,2,25},{y,-2,2}]

(Actually, my real problem is with the upper boundary of b -> Infinity,
but I would be happy with the b=25 approximation.)

In any case, when I type this into mathematica, I get the following
error:

   "NDSolve::ivnone: No initial values specified."


What is wrong?!  I know the above differential equation has an
analytical solution (I found it using the DSolve function!), but I am
trying to learn how to use NDSolve to solve such equations.

kenton at stanford.edu




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