Fourier series convergence question

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SUMMARY

The discussion focuses on the convergence of the Fourier series F(x) for the piecewise function f(x), defined as f(x) = 5 for -π ≤ x ≤ 0 and f(x) = 3 for 0 < x ≤ π. It concludes that F(x) fails to converge at the endpoints x = -π and x = π due to discontinuity, as demonstrated by the calculation F(-π) = 4, which does not equal f(-π) = 5. The reasoning provided confirms that the Fourier series does not match the function's value at these points, indicating a failure of convergence.

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Homework Statement



f(x) = 5, -pi <= x <= 0
f(x) = 3, 0 < x <= pi

f(x) is the function of interest

Find the x-points where F(x) fails to converge
to f(x)


Homework Equations



F(x) = f(x) if f is continuous at x\in(-L,L)
F(x) = 0.5[ f(x-) + f(x+) ] if f is discontinous at x\in(-L,L)

F(x) is the Fourier series of f(x)

The Attempt at a Solution



Would the Fourier series, F(x) fail to converge
at +pi and -pi ?

My reasoning is as follows

- At both -pi and +pi, we have the start and end value of f(x)

- By definition F(x) = (1/2)f(x-) + (1/2)f(x+)

- Let's take x = -pi, which means f(x) =5 and f(-x) = 3

- F(-pi) = (1/2)(5) + (1/2)(3) = 8/2 = 4 which is not equal to f(-pi)=5

- From the latter, we can conclude that F(-pi) fails to converge to
the value given from f(-pi) since their not equal to each other

Just want to check if my reasoning is ok since no answer was provided to this question

thanks
 
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