\(\left(5x-1\right)^2=16\Leftrightarrow\left[{}\begin{matrix}5x-1=-4\\5x-1=4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}5x=-3\\5x=5\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{3}{5}\\x=1\end{matrix}\right.\)
\(\left(5x-1\right)^2=16\)
\(=>\left(5x-1\right)^2=4^2\) hoặc \(=>\left(5x-1\right)^2=\left(-4\right)^2\)
\(=>5x-1=4\) \(=>5x-1=-4\)
\(=>5x=4+1\) \(=>5x=-4+1\)
\(=>5x=5\) \(=>5x=-3\)
\(=>x=5:5\) \(=>-3:5\)
\(=>x=1\) \(=>x=\dfrac{-3}{5}\)
\(#WendyDang\)
\(\left(5x-1\right)^2=16\)
\(\Rightarrow\left[{}\begin{matrix}\left(5x-1\right)^2=4^2\\\left(5x-1\right)^2=\left(-4\right)^2\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}5x-1\text{=}4\\5x-1\text{=}-4\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}5x\text{=}6\\5x\text{=}-3\end{matrix}\right.\)
\(\Leftrightarrow x\text{=}\dfrac{6}{5}hoặcx\text{=}\dfrac{-3}{5}\)
Vậy......
