Complex Fourier series has a singular term

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Ragnord
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Homework Statement



Find the complex Fourier series for f(t)=t(1-t), 0<t<1

Homework Equations



[tex]\sum_{n=-\infty}^{\infty}c_{n}e^{2in\pi t}[/tex]

where [tex]c_{n}=\int_{0}^{1}f(t)e^{-2in\pi t}dt[/tex]


The Attempt at a Solution



I've worked out that c[tex]_{n}=-1/(2n^2 \pi^2)[/tex]. The problem is that for n=0, it is singular. Is there some way around this or does it mean that the complex Fourier series doesn't exist?
I tried using maple to graph the series with the n=0 term omitted and it comes out to the right shape, but is shifted vertically down some, leading me to believe that the singular term should be replaced by a constant or something.
 
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[tex]c_0=\int_0^1 f(t)\,dt[/tex]
 
Well that was easy, just like a real Fourier series. Thanks.
I'm interested in knowing why that's the case though, I haven't seen anything about doing anything special for [tex]c_{0}[/tex] in anything I've seen about complex Fourier series.
 
Just plug in n=0 before integrating instead of after!