Đáp án:
\(\begin{array}{l}
a)m \ne - 2\\
c)m \ne \pm 2\\
b)m \ne 2\\
d)\left[ \begin{array}{l}
m = 1\\
m = - 1
\end{array} \right.\\
e)\forall m
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
a)DK:m + 2 \ne 0\\
\to m \ne - 2\\
c)DK:{m^2} - 4 \ne 0\\
\to \left( {m - 2} \right)\left( {m + 2} \right) \ne 0\\
\to m \ne \pm 2\\
b)DK:m - 2 \ne 0\\
\to m \ne 2\\
d)DK:{m^2} - 1 = 0\\
\to \left[ \begin{array}{l}
m = 1\\
m = - 1
\end{array} \right.\\
e)DK:{m^2} + 1 \ne 0\left( {ld} \right)\forall m\\
KL:\forall m
\end{array}\)
