Lời giải:
a) \(4x(x-1)=x-1\)
\(\Leftrightarrow 4x(x-1)-(x-1)=0\Leftrightarrow (x-1)(4x-1)=0\)
\(\Rightarrow \left[\begin{matrix} x-1=0\rightarrow x=1\\ 4x-1=0\rightarrow x=\frac{1}{4}\end{matrix}\right.\)
b) \(2x^3-50x=0\Leftrightarrow 2x(x^-25)=0\)
\(\Leftrightarrow 2x(x-5)(x+5)=0\)
\(\Rightarrow \left[\begin{matrix} x=0\\ x-5=0\rightarrow x=5\\ x+5=0\rightarrow x=-5\end{matrix}\right.\)
c) \(5x(2x-7)-14x=-49\)
\(\Leftrightarrow 5x(2x-7)-7(2x-7)=0\)
\(\Leftrightarrow (5x-7)(2x-7)=0\Rightarrow \left[\begin{matrix} 5x-7=0\rightarrow x=\frac{7}{5}\\ 2x-7=0\rightarrow x=\frac{7}{2}\end{matrix}\right.\)
