Help with found Fourier complex series of e^t

needved
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Homework Statement


i have this function
\begin{equation}
f(t) = e^t
\end{equation}

Homework Equations


[/B]
the Fourier seria have the form
\begin{equation}
f(t) = \sum C_{n} e^{int}
\end{equation}

The Attempt at a Solution

}
[/B]
so i need to find the coeficients $c_{n}$ given by
\begin{equation}
\frac{1}{2\pi} \int_{-\pi}^{\pi} f(t) e^{int} dt
\end{equation}

my attempts are try to find the coeficients doing integration by parts but i don't have anithing. Any help here please.

thanks in advance
 
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needved said:

Homework Statement


i have this function
\begin{equation}
f(t) = e^t
\end{equation}

Homework Equations


[/B]
the Fourier seria have the form
\begin{equation}
f(t) = \sum C_{n} e^{int}
\end{equation}

The Attempt at a Solution

}
[/B]
so i need to find the coeficients $c_{n}$ given by
\begin{equation}
\frac{1}{2\pi} \int f(t) e^{int} dt
\end{equation}

my attempts are try to find the coeficients doing integration by parts but i don't have anithing. Any help here please.

thanks in advance

(1)What is the interval over which you want the Fourier series? The series produces a periodic function of ##t##, but ##e^t## is not periodic on the whole line.
(2) You have an elementary integral that you ought to be able to solve almost by inspection. No fancy integration tools are needed, and certainly integration by parts is overkill.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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