Đề bài bị thiếu bạn ơi.
Có: \(3n-1⋮3n-4\)
\(\Rightarrow3n-4+3⋮3n-4\)
\(\Rightarrow3⋮3n-4\)
\(\Rightarrow3n-4\inƯ\left(3\right)=\left\{\pm1;\pm3\right\}\)
\(\Rightarrow n\in\left\{\frac{5}{3};1;\frac{7}{3};\frac{1}{3}\right\}\)
Vậy...
\(3n-1⋮3n-4\)
\(\Leftrightarrow3n-4+3⋮3n-4\)
\(\Leftrightarrow3⋮3n-4\)
\(\Leftrightarrow3n-4\inƯ\left(3\right)=\left\{\pm1;\pm3\right\}\)
3n - 4 | 1 | -1 | 3 | -3 |
3n | 5 | 3 | 7 | -1 |
n | 5/3 | 1 | 7/3 | -1/3 |