Fourier Series of a constant (Pi)?

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The discussion centers on determining the Fourier series for the function f(x) = π + x. It is clarified that the Fourier series of a constant, like π, is simply π because constants are periodic functions. The participants explore whether π can be expanded as a Fourier series, noting that it can be treated as a periodic function. The calculation involves finding the coefficients, where the constant term a0 equals 2π, while the other coefficients are zero. Ultimately, the conclusion is that the Fourier series representation for the constant π is indeed just π.
Major_Disaster
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Homework Statement


Determine the Fourier series of f(x) = pi + x


Homework Equations





The Attempt at a Solution


I see you have to calculate the two "series" separately and then add them. I know that the Fourier series of pi is just pi - but i was wondering why (i know that sounds ridicolous).

Is it simply a case of, pi is not perioidic so can't be expanded as a Fourier series so its just pi?

Or can you (as i have been trying and failing to do), somehow plug into the Fourier equations (for bn) show that the series is zero, but the a0 is 2pi, so its just pi?

Just interested is all...

Thanks
 
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The Fourier transform of a constant is that constants times the delta function, which is not really a function but a distribution (I'm assuming you're working over all of R).
 
Major_Disaster said:

Homework Statement


Determine the Fourier series of f(x) = pi + x

The Attempt at a Solution


I see you have to calculate the two "series" separately and then add them.
You don't have to calculate them separately.
I know that the Fourier series of pi is just pi - but i was wondering why (i know that sounds ridicolous).

Is it simply a case of, pi is not perioidic so can't be expanded as a Fourier series so its just pi?
A constant function f(x)=c is periodic because f(x)=c=f(x+T).
Or can you (as i have been trying and failing to do), somehow plug into the Fourier equations (for bn) show that the series is zero, but the a0 is 2pi, so its just pi?

Just interested is all...

Thanks
Yes, that's exactly what you do.
 
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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