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Homework Help: Schrodinger equation

  1. Apr 24, 2010 #1
    ive been asked to show that the function of Y(x) = A sin (x) = 0 is a solution to the equation of

    d2Y(x)
    dx2

    +k2Y(x)=0

    where the Y is meant to be the lowercase wavefunctio psi....i just cant get it to work on this :(

    basiaclly im completly stuck. Im not really sure what to do!! any help would be much appreciated :)

    many thanks
     
  2. jcsd
  3. Apr 24, 2010 #2

    Cyosis

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    You're supposed to plug Y(x) into the differential equation and compute the derivatives.
     
  4. Apr 24, 2010 #3
    yer thats what ive just been reading but i am unsure of the value of Y

    thanks for quick reply :)
     
  5. Apr 24, 2010 #4
    sorry what i meant was that i am unsure of the value of A in th function. I understand kind of how to do the rest its just the A that has thrown me

    and also i made a mistake the function is Y(x) = A sin (kx) not as stated above
     
  6. Apr 24, 2010 #5

    Cyosis

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    The A is a constant. It will be pretty obvious what that A is when you plug the solution into the differential equation. Do this and please show your work. I can't say much more until you have done that without giving away the answer.
     
    Last edited: Apr 24, 2010
  7. Apr 24, 2010 #6
    is a just the quatum numbers (n=1,2,3...)
    ha ha i bet its right in front of me isnt it
     
  8. Apr 24, 2010 #7

    Cyosis

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    Why aren't you plugging the solution into the differential equation as I have asked you to do three times now?
     
  9. Apr 28, 2010 #8
    Try doing it the other way round: try taking the solution, and differentiating it twice. See what that gives you.
     
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