Hi I am trying to find an expression for X(f), when, x(t)=exp(-σt)sin(2∏f1t) I have attached a screen shot of what I have worked out, but it doesn't seem to be coming together very vell, is there something I am missing in the steps? Or am I right, and how would I integrate that? thanks.
The Fourier transform of per table of transforms is The u(t) bit tells you the limits of integration are from 0 to plus infinity - otherwise there is no solution if the lower limit goes to minus infinity . The problem can be solved using repeated integration by parts. Not sure if this is the same as your problem - given your equation has no reference to the u(t) term - i.e. the Heavyside Function.
Hi, Thanks for your reply, I have attached another JPEG, I have come up with an expression but not sure if it is correct, I did mean to put the limits from 0 to infinity sorry about that. However, when i put this into matlab to plot the X(f), i just comes out wrong.