Phương trình ${{\log }_{a}}f\left( x \right)={{\log }_{a}}g\left( x \right),a>0,a\ne 1$ tương đương với
A.$\left\{ \begin{align}
& f\left( x \right)=g\left( x \right) \\
& f\left( x \right)\ge 0 \\
\end{align} \right.$
B.\(\left\{ \begin{align}
& f\left( x \right)=g\left( x \right) \\
& g\left( x \right)\ge 0 \\
\end{align} \right.\)
C.$f\left( x \right)=g\left( x \right)$
D.$\left\{ \begin{align}
& f\left( x \right)=g\left( x \right) \\
& f\left( x \right)>0 \\
\end{align} \right.$
A.$\left\{ \begin{align}
& f\left( x \right)=g\left( x \right) \\
& f\left( x \right)\ge 0 \\
\end{align} \right.$
B.\(\left\{ \begin{align}
& f\left( x \right)=g\left( x \right) \\
& g\left( x \right)\ge 0 \\
\end{align} \right.\)
C.$f\left( x \right)=g\left( x \right)$
D.$\left\{ \begin{align}
& f\left( x \right)=g\left( x \right) \\
& f\left( x \right)>0 \\
\end{align} \right.$
Loga
Hóa Học lớp 12
