Fourier Cosine Series: Equivalence for {x}

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Discussion Overview

The discussion revolves around the Fourier cosine series correspondence for the function f(x) = x within the interval (0, π). Participants are exploring the conditions under which this correspondence can be considered an equality and how to express the function in terms of its Fourier series representation.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Homework-related

Main Points Raised

  • One participant presents a Fourier cosine series for f(x) = x and asks for clarification on why this correspondence is an equality for 0 ≤ x ≤ π.
  • Another participant expresses confusion about how to approach the problem and indicates they are unsure where to start.
  • Several posts attempt to clarify the mathematical notation used in the problem, aiming to make it more readable for others.
  • A participant shares a link to external notes on Fourier series and integral transforms, suggesting it may be helpful for understanding the topic.

Areas of Agreement / Disagreement

The discussion does not appear to reach a consensus, as participants express varying levels of understanding and clarity regarding the problem. There is no agreement on the specific conditions or implications of the Fourier cosine series correspondence.

Contextual Notes

Participants have not fully resolved the mathematical steps or assumptions required to establish the equality in question, and there are indications of uncertainty regarding the notation and concepts involved.

Joystar77
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2. Fourier cosine series correspondence for f(x)= x, o < x < pi given by x ~ pi / 2 - 4/n, E infinity on top and n=1 on bottom. cos (an-1)/x / (2n-1)squared, (0 < x < pi).

Explain why this correspondence is actually an equality for 0 is less than or equal to x and x is less than or equal to pi. Then explain how we can write

{x} = pi /2 - 4 / n E infinity on top and n=1 on bottom

cos (2n - 1)x/ (2n-1) squared, (-n is less than or equal to x and x is less than or equal to pi)
 
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Sorry, I forgot to mention in the original thread that I am totally lost and don't know where to start at with this problem.
 
Here is the above problem and I hope that its easier to read. I used some Mathematical symbols, so hope that you can understand it. Any questions, then please ask me if your unable to understand or read the problem.

Fourier cosine series correspondence for f (x) = x, o < x < Pie given by x ~ Pie / 2 – 4 / n

∑_(n=1)^∞▒cos⁡〖(2n-1)x/(2n-1)〗 〖^2〗,(o<x<Pie)

Explain why this correspondence is actually an equality for 0 ≤ x ≤ Pie. Then explain how we can write

[x] = Pie / 2 – 4 / n ∑_(n=1)^∞▒cos⁡〖(2n-1)x/(2n-1)〗 〖^2〗 ( -n ≤ x ≤ Pie)
 
Joystar1977 said:
Here is the above problem and I hope that its easier to read. I used some Mathematical symbols, so hope that you can understand it. Any questions, then please ask me if your unable to understand or read the problem.

Fourier cosine series correspondence for f (x) = x, o < x < Pie given by x ~ Pie / 2 – 4 / n

∑_(n=1)^∞▒cos⁡〖(2n-1)x/(2n-1)〗 〖^2〗,(o<x<Pie)

Explain why this correspondence is actually an equality for 0 ≤ x ≤ Pie. Then explain how we can write

[x] = Pie / 2 – 4 / n ∑_(n=1)^∞▒cos⁡〖(2n-1)x/(2n-1)〗 〖^2〗 ( -n ≤ x ≤ Pie)
http://mathhelpboards.com/math-notes-49/fourier-series-integral-transform-notes-2860.html
 
Thanks! I will take a look at these Fourier Series Integral Transform Notes.

dwsmith said:
http://mathhelpboards.com/math-notes-49/fourier-series-integral-transform-notes-2860.html
 

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