\(\dfrac{3n-4}{2n+1}\in Z\\ \Rightarrow\left(3n-4\right)⋮\left(2n+1\right)\\ \Rightarrow\left(6n-8\right)⋮\left(2n+1\right)\\ \Rightarrow\left(6n+3-11\right)⋮\left(2n+1\right)\\ \Rightarrow\left[3\left(2n+1\right)-11\right]⋮\left(2n+1\right)\)
Vì \(3\left(2n+1\right)⋮\left(2n+1\right)\Rightarrow-11⋮\left(2n+1\right)\Rightarrow2n+1\inƯ\left(-11\right)\)
Ta có bảng:
| 2n+1 | -11 | -1 | 1 | 11 |
| n | -6 | -1 | 0 | 5 |
Vậy \(n\in\left\{-6;-1;0;5\right\}\)
Chọn A
Đúng 0
Bình luận (0)
