Add function graphs

tikz/exponential-functions/exponential-functions.tex

@@ -0,0 +1,40 @@
+\documentclass[varwidth=false, border=2pt]{standalone}
+
+\usepackage{pgfplots}
+\pgfplotsset{compat=1.17}
+\usepackage{tikz}
+\usepackage{nicefrac}
+\pgfplotsset{every axis legend/.append style={
+at={(0,0)},
+anchor=north east}}
+
+\begin{document}
+\begin{tikzpicture}
+    \begin{axis}[
+        axis x line=middle,
+        axis y line=middle,
+        grid = major,
+        width=16cm,
+        height=8cm,
+        grid style={dashed, gray!30},
+        xmin=-2.1,   % start the diagram at this x-coordinate
+        xmax= 4.1,   % end   the diagram at this x-coordinate
+        ymin= 0,     % start the diagram at this y-coordinate
+        ymax= 17,    % end   the diagram at this y-coordinate
+        xlabel=$x$,
+        ylabel=$y$,
+        ytick={0,2,3,4,8,9,12,16},
+        yticklabels={0,2,3,4,8,9,12,16},
+        legend cell align=left,
+        legend pos=south east,
+        legend style={draw=none},
+        tick align=outside,
+        enlargelimits=false]
+      % plot the function
+      \addplot[domain=-2:4, red, ultra thick,samples=500] {2^x};
+      \addplot[domain=-2:4, green!50!black, ultra thick,dashed,samples=500] {3^x};
+      \addplot[domain=-2:4, blue, ultra thick,dotted,samples=500] {4^x};
+      \legend{$2^x$,$3^x$,$4^{x}$}
+    \end{axis}
+\end{tikzpicture}
+\end{document}