Đáp án:
\(\begin{array}{l}
B8:\\
\left\{ \begin{array}{l}
x > 0\\
x \ne 1
\end{array} \right.\\
B9:\\
\left\{ \begin{array}{l}
x \ge 0\\
x \ne 1
\end{array} \right.
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
B8:\\
a)DK:\left\{ \begin{array}{l}
\sqrt x > 0\\
x - 1 \ne 0
\end{array} \right.\\
\to \left\{ \begin{array}{l}
x > 0\\
x \ne 1
\end{array} \right.\\
B9:\\
a)DK:\left\{ \begin{array}{l}
x \ge 0\\
\sqrt x - 1 \ne 0
\end{array} \right.\\
\to \left\{ \begin{array}{l}
x \ge 0\\
x \ne 1
\end{array} \right.
\end{array}\)
