a/ \(4^x=2^{x+1}\)
\(\Leftrightarrow\left(2^2\right)^x=2^{x+1}\)
\(\Leftrightarrow2^{2x}=2^{x+1}\)
\(\Leftrightarrow2x=x+1\)
\(\Leftrightarrow2x-x=1\)
\(\Leftrightarrow x=1\left(tm\right)\)
Vậy -.
b/ \(16=\left(x-1\right)^4\)
\(\Leftrightarrow\left[{}\begin{matrix}\left(x-1\right)^4=4^4\\\left(x-1\right)^4=\left(-4\right)^4\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x-1=4\\x-1=-4\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=5\\x=-3\end{matrix}\right.\)
Vậy ...
c/ bí
