\documentclass{book}
\usepackage{rotating}
\usepackage{tikz}
\begin{document}
\begin{minipage}[t]{.15\linewidth}
\begin{center}
\begin{tikzpicture}[ scale=2]
 % axis
\draw [-,dashed](0,-.5) -- (0,.5) node(yline)[above] {};
\draw [-,thick] (.05,-.5) to [out=90,in=-135] (.3,.2) ;
\draw [-,thick] (-.05,-.5) to [out=90,in=-50] (-.3,.2) ;
 \end{tikzpicture}
\end{center}
\end{minipage} 
\begin{rotate}{180}
\begin{minipage}[t]{.15\linewidth}
\begin{center}
\begin{tikzpicture}[ scale=2]
 % axis
\draw [-,dashed](0,-.5) -- (0,.5) node(yline)[above] {};
\draw [-,thick] (.05,-.5) to [out=90,in=-135] (.3,.2) ;
\draw [-,thick] (-.05,-.5) to [out=90,in=-50] (-.3,.2) ;
 \end{tikzpicture}
\end{center}
\end{minipage} \\
\end{rotate}
\begin{minipage}[t]{.15\linewidth}
\begin{center}
\begin{tikzpicture}[ scale=2]
 % axis
\draw [-,dashed](0,-.5) -- (0,.5) node(yline)[above] {};
\draw [-,thick] (.05,.5) to [out=110,in=-145] (.3,.1) ;
\draw [-,thick] (-.05,-.5) to [out=90,in=-50] (-.3,.1) ;
 \end{tikzpicture}
\end{center}
\end{minipage} 
\begin{rotate}{90}
\begin{minipage}[t]{.15\linewidth}
\begin{center}
\begin{tikzpicture}[ scale=2]
 % axis
\draw [-,dashed](-.5,0) -- (.5,0) node(yline)[above] {};
\draw [-,thick] (.05,.5) to [out=110,in=-145] (.3,.1) ;
\draw [-,thick] (-.05,-.5) to [out=90,in=-50] (-.3,.1) ;
 \end{tikzpicture}
\end{center}
\end{minipage} 
\end{rotate}
\end{document}