Fourier Transform deduce the following transform pair

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SUMMARY

The discussion focuses on applying the similarity and shift theorems to derive the Fourier transform of the function cos(πx) / π(x - 0.5). The transform is established as e^(-iπs) * Π(s), where Π(s) represents the rectangular function. Key insights include the application of the similarity theorem, which states that f(ax) has a transform of (1/a)F(s/a), and the shift theorem, which indicates that f(x - a) has a transform of e^(-i2πas)F(s). The challenge lies in correctly incorporating the rectangular function into the transform.

PREREQUISITES
  • Understanding of Fourier Transform principles
  • Familiarity with the similarity theorem in Fourier analysis
  • Knowledge of the shift theorem in Fourier analysis
  • Basic concepts of impulse functions and rectangular functions
NEXT STEPS
  • Study the properties of the Fourier Transform, focusing on the similarity theorem
  • Explore the shift theorem in greater detail with practical examples
  • Learn about impulse functions and their Fourier transforms
  • Investigate the properties and applications of the rectangular function (Π function)
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Students and professionals in signal processing, mathematicians, and engineers looking to deepen their understanding of Fourier transforms and their applications in analyzing signals.

grandpa2390
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Homework Statement


I'm supposed to be using the similarity theorem and the shift theorem to solve:

cos(πx) / π(x-.5) has transform e^(-iπs)*Π(s)

Homework Equations


similarity theorem f(ax) has transform (1/a)F(s/a)
shift theorem f(x-a) has transform e^(-i2πas)F(s)

The Attempt at a Solution


I don't know. cos(πx) has the impulse pair transform and the impulse pair function has cos(πs) transform.
the only term that I can get is that the shift theorem will give me a e^(-iπs) because the 1/2 in the impulse function. I don't understand how to get the rect(s) term in the transform.
 
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Use the fact that ##\sin(\pi x - \frac{\pi}{2}) = -\cos(\pi x)##.
 
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Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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