\begin{array}{|ccc|}a_1&a_2&a_3\\ b_1&b_2&b_3\\ c_1&c_2&c_3\end{array} enclosed by double dollar symbol is \(\begin{array}{|ccc|}a_1&a_2&a_3\\ b_1&b_2&b_3\\ c_1&c_2&c_3\end{array}\)
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