[NumCS] Small addition

semester3/numcs/parts/01_interpolation/01_trigonometric/00_fourier.tex

@@ -108,6 +108,7 @@ Die dargestellte Funktion ist die Fourier-Reihe der charakteristischen Funktion
 \begin{align*}
     b - a + \frac{1}{\pi} \sum_{k \neq 0} e^{-ikc}\frac{\sin(kd)}{k} e^{i2\pi kt}, \mediumhspace t \in [0, 1]
 \end{align*}
+Mit $c = \pi(a + b)$ und $d = \pi(b - a)$
 
 % TODO: Replace with rendered image from matplotlib (will be higher quality than screenshot from script and can tweak it to our liking)
 % we will have it anyway after solving the exercises, so might as well