Question

|4-x|=2x-1

Answer 1

\(\Leftrightarrow\left[{}\begin{matrix}4-x=2x-1\left(x\le4\right)\\x-4=2x-1\left(x>4\right)\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{3}\left(thỏa-mãn\right)\\x=-3\left(ktm\right)\end{matrix}\right.\)

Vậy \(x=\dfrac{5}{3}\)

Answer 2

đkxđ: \(2x-1\ge0\)\(\Rightarrow x\ge\dfrac{1}{2}\)

\(\left[{}\begin{matrix}4-x=2x-1\\4-x=-2x+1\end{matrix}\right.\)

\(\left[{}\begin{matrix}x=\dfrac{5}{3}\\x=-3\end{matrix}\right.\)(tm); x=-3( loại)

vậy tập nghiệm pt là S= \(\left\{\dfrac{5}{3}\right\}\)