Fourier Transform of x(t) and g(t) with Product Calculation

nikki92
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Homework Statement


x(t) = 5cos(2*pi*1000*t) and g(t) = ∑ from n=-infinity to infinity delta(t-n/10000)

find Fourier transform of x(t) and g(t) and the product of the two


The Attempt at a Solution



x(w) = 5*sqrt(pi/2) [delta(w-2000pi)+delta(w+2000pi)]

g(w) = 1

so would the product of the two just be the x(w) ?
 
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nikki92 said:

Homework Statement


x(t) = 5cos(2*pi*1000*t) and g(t) = ∑ from n=-infinity to infinity delta(t-n/10000)

find Fourier transform of x(t) and g(t) and the product of the two


The Attempt at a Solution



x(w) = 5*sqrt(pi/2) [delta(w-2000pi)+delta(w+2000pi)]

g(w) = 1

so would the product of the two just be the x(w) ?
##G(\omega)## isn't equal to 1. That's the Fourier transform of a single delta function. You have a train of delta functions.
 
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