Fourier Transforms: Proving Proportionality

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1. We consider the on shell wave packet:
\varphi(t,x)=\int\frac{dk}{2\pi}exp(-\frac{(k-k_{0})^{2}}{\Delta k^{2}}+ik(t-x))dk<br />

I need to show it is proportional to:
exp(ik_{0}(t-x)-\frac{\triangle k^{2}}{4}(t-x)^{2})dk
through a Fourier transform of the gaussian


3. I used a Fourier transform of the form e^(ikx) but this doesn't seem to give me the right answer as I end up with something proportional to exp(-\frac{(k-k_{0})^{2}}{\triangle k^{2}}+ikt)dk before integrating
 
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Show us what you think the integral for ##\varphi(t,k)## is.
 
Solved it! :-)...

However I now need to solve this:

\int\frac{dk}{2\pi}exp(-\frac{(k-k_{o})^{2}}{\triangle k^{2}}+ik(pt-x)


where p=1-\frac{h_{00}}{2}-h_{01}-\frac{h_{11}}{2}

by using Fourier transforms
 
Solved this one too now :-)

Not sure how to graph it though...
 
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