Đáp án:
\(TXD:D = R\backslash \left\{ {\dfrac{\pi }{{12}} + \dfrac{{k\pi }}{6}} \right\}\)
Giải thích các bước giải:
\(\begin{array}{l}
y = tan6x - 1\\
DK:\cos 6x \ne 0\\
\to 6x \ne \dfrac{\pi }{2} + k\pi \\
\to x \ne \dfrac{\pi }{{12}} + \dfrac{{k\pi }}{6}\left( {k \in Z} \right)\\
\to TXD:D = R\backslash \left\{ {\dfrac{\pi }{{12}} + \dfrac{{k\pi }}{6}} \right\}
\end{array}\)
