Fourier integral / transform ? What is it really?

AI Thread Summary
The discussion focuses on finding phi(k) using Fourier transforms. A student seeks guidance on applying the Fourier transform and is advised to set t = 0, multiply by e^{-i k' x}, and integrate over x. This approach leads to an integrand that produces a delta function, simplifying the k integral. The student expresses uncertainty about completing the square in the exponential after manipulating the equation. The response confirms that completing the square is indeed the next step to simplify the expression further.
student1938
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Find phi(k)

I need help with this question as far as what am I looking for and how do I use a Fourier transform cause I think I need one.

student
 

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Any suggestions guys?
 
Set t = 0, multiply both sides by
e^{-i k' x}
and integrate over x. The integrand
e^{i(k-k')x}
in the x integral will yield a delta function which let's you evaluate the k integral.
 
try completing the square in the exponential...
 
If i multiple both sides by exp(-ik'x) the LHS gives exp(-ik'x-(x/2a)^2). I' m not sure what to do with this to simplify it further. Do i have to try to complete the square in this exponential now?
 
student1938 said:
If i multiple both sides by exp(-ik'x) the LHS gives exp(-ik'x-(x/2a)^2). I' m not sure what to do with this to simplify it further. Do i have to try to complete the square in this exponential now?

Yes, that's what Dr T was suggesting.
 
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