a, \(\left(x-1\right)^2=4\Leftrightarrow\left[{}\begin{matrix}x-1=2\\x-1=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-1\end{matrix}\right.\)
b, \(\left(2x+1\right)^3=5^3\Rightarrow2x+1=5\Leftrightarrow x=2\)
c, \(\left(x-5\right)^5=3^5\Rightarrow x-5=3\Leftrightarrow x=8\)