% Author: Prof. Dr. Matthias Jung, DL9MJ
% Year: 2023
\pgfkeys{/pgf/number format/.cd,1000 sep={}}
\begin{tikzpicture}
    \begin{axis}[
        axis lines=center, 
        axis line style={-Triangle},
        width=\linewidth,
        height=6cm,
        xmin=0,
        xmax=60,
        ymin=-3,
        ymax=3,
        ticks=none,
        xlabel={$t$},
        xlabel style={anchor=north},
        ylabel={$U$},
        ylabel style={anchor=east},
    ]
    \addplot[smooth, mark=none, DARCred, thick, domain=0:60, samples=400] {sin(0.20*deg(x))}; 
    \addplot[smooth, mark=none, DARCgreen, thick, domain=0:60, samples=400] {sin(0.30*deg(x))}; 
    \addplot[smooth, mark=none, DARCblue, thick, domain=0:60, samples=400] {sin(0.40*deg(x))}; 
    \end{axis}
\end{tikzpicture}