\begin{tikzpicture}[line cap=round,line join=round,x=1cm,y=1cm] \tikzset{ every pin/.style={fill=yellow!50!white,rectangle,rounded corners=3pt,font=\tiny}, small dot/.style={fill=black,circle,scale=0.3},} \begin{axis}[ x=2cm,y=2cm, axis lines=middle, axis line style = {-latex}, xmin=-0.5, xmax=3, ymin=-0.5, ymax=2, ytick=\empty, xtick=\empty, xlabel=$x$, ylabel=$y$, extra x ticks={1.3}, extra x tick style={ tick label style={anchor=north}}, extra x tick labels={$x_0$}, extra y ticks={1.14}, extra y tick style={ tick label style={anchor=east}}, extra y tick labels={$\displaystyle \sqrt{x_0}$}, enlargelimits = true, ] \draw [thick, dashed] (axis cs: -0.05,1.14) -- (axis cs: 1.3,1.14); \draw [thick, dashed] (axis cs: 1.3,-0.05) -- (axis cs: 1.3,1.14); \node[label={180:{}},circle,fill,inner sep=1.5] at (axis cs:1.3,1.14) {}; \node[label={300:{$0$}},circle,fill,inner sep=1.5] at (axis cs:0,0) {}; % node[pos=0.5, above] {$y=12$}; % \addplot coordinates { (0,1.14) (1.3,1.14) }; % \addplot coordinates { (1,4) (2,6) }; % \draw (axis cs:2,3) -- node[left]{Text} (axis cs:2,6); \addplot[domain=0:2, blue, line width=1,samples=5000] {sqrt(x)}; %\addplot[domain=-3.8:-0.05, red, line width=1,samples=5000] {sin(deg(1/(x)))}; \begin{scriptsize} \node () at (axis cs:2.2,1.7) {$\displaystyle y=\sqrt{x}\;(x \neq 0)$}; \end{scriptsize} % \draw[] (axis cs:1.3, 0.1) -- (axis cs:1.3, -0.1); % \node () at (axis cs:1.3,-0.25) {$x_0$}; % \draw[] (axis cs:1.14,-0.05) -- (axis cs:1.14, 0.05); % \node () at (axis cs:0.33,-0.45) {$\frac{1}{\pi}$}; \end{axis} \end{tikzpicture}