\(5^{x-1}< 1000\)
\(\Rightarrow5^{x-1}< 5^1< 5^2< 5^3< ,5^4< 1000\)
\(\Rightarrow\left[{}\begin{matrix}x-1=1\\x-1=2\\x-1=3\\x-1=4\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=2\\x=3\\x=4\\x=5\end{matrix}\right.\)
Vậy....
( mk ko chắc đúng hay sai nx )