The Attempt at a Solution
I tried to attempt the question but I am not sure how to start it, at least for part (i).
My biggest question, I think, is how does the multiplication of a random complex number to a Fourier-Transformed signal (V(f)) have an effect on V(f)? Although the question did not specify the type of signal that has been Fourier-Transformed, I shall assume that the original signal is a cosine waveform, as shown below:
In the question, it also mentioned to visualise V(f) and cV(f) as vectors in the complex plane, but how should I do it? Are there any diagrams online that show me how to represent cV(f) and V(f) as vectors in the complex plane?
Thank you. :)