Câu hỏi

  • A \(\begin{array}{l}
    a)\,\,m > 3\\
    b)\,\,m \ne 4
    \end{array}\)
  • B \(\begin{array}{l}
    a)\,\,m > 3\\
    b)\,\,m \ne 1
    \end{array}\)
  • C \(\begin{array}{l}
    a)\,\,m \ge 3\\
    b)\,\,\left\{ \begin{array}{l}
    m \ne 1\\
    m \ne 4
    \end{array} \right.
    \end{array}\)
  • D \(\begin{array}{l}
    a)\,\,m > 3\\
    b)\,\,\left\{ \begin{array}{l}
    m \ne 1\\
    m \ne 4
    \end{array} \right.
    \end{array}\)

Lời giải chi tiết:

\(\eqalign{& a)\,\,DK:\left\{ \matrix{m - 3 \ge 0 \hfill \cr m - 3 \ne 0 \hfill \cr} \right. \Leftrightarrow m > 3 \cr & b)\,\,DK:\left\{ \matrix{{{1 - m} \over {4 - m}} \ne 0 \hfill \cr 4 - m \ne 0 \hfill \cr} \right. \Leftrightarrow \left\{ \matrix{1 - m \ne 0 \hfill \cr 4 - m \ne 0 \hfill \cr} \right. \Leftrightarrow \left\{ \matrix{m \ne 1 \hfill \cr m \ne 4 \hfill \cr} \right. \cr} \)


Luyện Bài Tập Trắc nghiệm Toán 9 - Xem ngay