The value of a Fourier series at a jump point (discontinuity)

Amaelle
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Homework Statement
calculate the value of the fourier serie at x=e for the e periodic function (0,e]
f(x)=log(x)
Relevant Equations
Fourier serie
Greetings
according to the function we can see that there is a jump at x=e and I know that the value of the function at x=e should be the average between the value of f(x) at this points
my problem is the following
the limit of f(x) at x=e is -infinity and f(e)=1
how can we deal with such situations?

thank you!
 
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Since ##f(0^+) = -\infty##, your function doesn't satisfy the Dirichlet conditions, so the usual theorem about convergence doesn't apply.
 
LCKurtz said:
Since ##f(0^+) = -\infty##, your function doesn't satisfy the Dirichlet conditions, so the usual theorem about convergence doesn't apply.
thanks a million!
 
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