Quick question about solving an eigenvalue problem

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Hakkinen
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I just have a question about the problem for when the eigenvalue = 0

Homework Statement


for [itex]y_{xx}=-\lambda y[/itex] with BC [itex]y(0)=0 , y'(0)=y'(1)[/itex]



Homework Equations




The Attempt at a Solution


y for lamda = 0 is ax+b
so from BC:
y(0)=b=0

and a=a

What is the conclusion to make from this? lamda = 0 and the eigenfunction is constant?
 
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Hakkinen said:
I just have a question about the problem for when the eigenvalue = 0

Homework Statement


for [itex]y_{xx}=-\lambda y[/itex] with BC [itex]y(0)=0 , y'(0)=y'(1)[/itex]



Homework Equations




The Attempt at a Solution


y for lamda = 0 is ax+b
so from BC:
y(0)=b=0

and a=a

What is the conclusion to make from this? lamda = 0 and the eigenfunction is constant?

I think the conclusion is just that y(x)=ax. That doesn't make it constant.
 
Dick said:
I think the conclusion is just that y(x)=ax. That doesn't make it constant.

Thanks for the reply. So the eigenvalue is 0 and the eigenfunction is just ax, with a determined by some IV?
 
Hakkinen said:
Thanks for the reply. So the eigenvalue is 0 and the eigenfunction is just ax, with a determined by some IV?

Well, you don't conclude that the eigenvalue is 0, you were given that, right? And, yes, you can conclude that y(x)=ax. You can't determine a from the conditions you are given. Another IV would do it.