\documentclass{article}
\usepackage{mathtools}
\usepackage{xepersian}

\begin{document}


\begin{table}
\centering
\begin{tabular}{cccc}
\hline
$N=9$&$N=7$&\text{جواب دقیق}&$x_{i}$\\
\hline
0.3678794515&0.3678794515&0.3678794515&$-1.0$\\
0.3678794515&0.3678794515&0.3678794515&$-0.8$\\
0.3678794515&0.3678794515&0.3678794515&$-0.6$\\
0.3678794515&0.3678794515&0.3678794515&$-0.4$\\
&&&\\
0.3678794515&0.3678794515&0.3678794515&$-0.2$\\
0.3678794515&0.3678794515&0.3678794515&$0$\\
0.3678794515&0.3678794515&0.3678794515&$0.2$\\
0.3678794515&0.3678794515&0.3678794515&$0.4$\\
\hline
\end{tabular}
\caption{}
\end{table}


\end{document}