\documentclass{ctexbeamer}
\usepackage{tikz}
\usepgflibrary{fpu}
\begin{document}
\begin{frame}{fpu库与画箭头冲突}
\begin{center}
    \begin{tikzpicture}[thick, scale=0.8, font=\footnotesize]
        \pgfkeys{/pgf/fpu, /pgf/fpu/output format=fixed}
        \path[use as bounding box] (-6.5,-3.5) -- (6.6,3.5);
        \draw[very thin,color=gray] (-6,-3) grid (6,3);
        \draw[thin,->] (-6.5,0) -- (6.6,0) node[right] {$x$};
        \draw[thin,->] (0,-3.2) -- (0,3.2) node[above] {$y$};
        \draw plot[domain=-6.28:6.28,samples=50]
        (\x,{sin(\x r)}) node[above=7mm] {$y=\sin x$};
        \draw[red] plot[domain=-6:6,samples=60]   
            (\x,{\x-(1/3!)*(\x)^3+(1/5!)*(\x)^5-(1/7!)*(\x)^7+(1/9!)*(\x)^9-(1/11!)*(\x)^11})   
            node[left,inner sep=1pt,red]{$y=x - \frac1{3!}x^3 + \frac1{5!}x^5 - \frac1{7!}x^7+\frac1{9!}x^9-\frac1{11!}x^{11}$};
        \end{tikzpicture}
\end{center}
\end{frame}
\end{document}

系统：texlive2019，用 xelatex 编绎，出错信息如下：

Package PGF Math Error: Sorry, an internal routine of the floating point unit

 got an ill-formatted floating point number `0.0'. The unreadable part was near

 '0.0'..

将

  \draw[thin,->] (-6.5,0) -- (6.6,0) node[right] {$x$};
  \draw[thin,->] (0,-3.2) -- (0,3.2) node[above] {$y$};

改为

 \draw[thin] (-6.5,0) -- (6.6,0) node[right] {$x$};
 \draw[thin] (0,-3.2) -- (0,3.2) node[above] {$y$};

即可通过编绎