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Homework Help: Positive oscillatory solution

  1. Sep 7, 2011 #1
    1. The problem statement, all variables and given/known data
    For the oscillatory solution (+k2) solution, suppose x is restricted to 0[itex]\leq[/itex]x[itex]\leq[/itex]a by requiring [itex]\psi[/itex](x)=0 and [itex]\psi[/itex](a)=0, what are the restrictions on A,B and k?


    2. Relevant equations
    given [itex]\psi[/itex](x)=Acos(kx)+Bsin(kx)


    3. The attempt at a solution
    so, I pretty just plugged in the zero values to get A must be zero, leaving only [itex]\psi[/itex](a)=0=Bsin(kx), which implies that B=0 and thus k can be 0 or pi, which seems to be a completely unreasonable result, so I am confused as to where I went wrong? Thanks
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Sep 7, 2011 #2

    LCKurtz

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    Gold Member

    You have 0 = sin(ka) not sin(kx). So ka can be any integer multiple of pi: k = nπ/a.
     
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