Hi everyone,(adsbygoogle = window.adsbygoogle || []).push({});

I am new to Physics Forums so please excuse me - I am so embarrassed that I can't do this integral, but its quite urgent and so if anyone here could help me I would be much obliged!

The integral I must carry out is:

[tex] \int_{-\infty}^{\infty}e^{-ax^{2}}\,\text{cos}kx\,dx [/tex]

I already know that the solution is

[tex] \sqrt{\frac{\pi}{a}}e^{-k^{2}/4a} [/tex]

But the task is to find out how one can get to this answer...I think the hint is in:

[tex] \int_{-\infty}^{\infty}e^{-ax^{2}}\,dx =\sqrt{\frac{\pi}{a}} [/tex]

which is from the standard Gaussian distribution.

Any information would be much appreciated!

Thank you,

Bladibla.

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# Homework Help: Help with integration!

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