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$$ f(t)={1 \over
T}\sum_{q=-\infty}^{q=\infty}c_q*e^{(2*\pi*i*q*t/T)}={1 \over T}
\sum_{q=-\infty}^{q=\infty}c_q*e^{(i*\Omega_q*t)},\hspace{1cm}
\Omega_q=2*\pi*q/T \hspace{1cm} (1) $$
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