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- Feb 5, 2012

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Hi Poirot,let x be the parameter in some interval and let lambda tend to infinity. Should I treat x as of the same order as constants, i.e x=O(1)?

I am sorry but I don't understand your question. Are you taking about the WKB approximation method? Can you please elaborate further?

Kind Regards,

Sudharaka.

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This is indeed what I am talking about Sudharaka. I have two questions for you- one which can be best illustrated by an example. For large t, find wkb approximation ofHi Poirot,

I am sorry but I don't understand your question. Are you taking about the WKB approximation method? Can you please elaborate further?

Kind Regards,

Sudharaka.

$y''-y(t^{2}x^{2}+tx^{-1})=0$ for x not zero

We do this by substituting y=exp(.....) (I'm sure you're familiar with this) and finding dominant balances. In the second dominant balance equation, I had potential driving terms t and t/x, and I thought both should be retained in the dominant balance as they are both of O(t). But the answer was wrong and it was clear that I should only retain t.

Why?

My second (and original) question is if I have to choose between x and a constant between retained in the dominant balance, ought I to retain both? I.e. x=O(1)