I need to plot the following function using Tikz:
but I don't know how to add the max and min lines at the function's bounds. This is the code I've written so far:
\begin{tikzpicture}
\begin{axis}[
xmin = 0, xmax = 30,
ymin = -1.5, ymax = 2.0,
]
\addplot[
domain = 0:30,
samples = 200,
smooth,
thick,
black,
] {exp(-x/10)*( cos(deg(x)) + sin(deg(x))/40 )};
\end{axis}
\end{tikzpicture}
and this is the output plot: