Giaỉ hộ bạn Trần Nhật Tiến\(a,\dfrac{12}{3n-1}\in Z\)\(\Rightarrow3n-1\inƯ\left(12\right)\)\(\Rightarrow3n-1\in\left\{-12;-6;-4;-3l-2;-1;1;2;3;4;6;12\right\}\)\(\Rightarrow n\in\left\{1;0;-1\right\}\)b) \(\dfrac{2n+3}{7}\in Z\)\(\Rightarrow2n+3⋮7\)\(\Rightarrow2\left(n-2\right)+7⋮7\)\(\Rightarrow n-2⋮7\)\(\Rightarrow n=7k+2\left(k\in...
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Giaỉ hộ bạn Trần Nhật Tiến
\(a,\dfrac{12}{3n-1}\in Z\)
\(\Rightarrow3n-1\inƯ\left(12\right)\)
\(\Rightarrow3n-1\in\left\{-12;-6;-4;-3l-2;-1;1;2;3;4;6;12\right\}\)
\(\Rightarrow n\in\left\{1;0;-1\right\}\)
b) \(\dfrac{2n+3}{7}\in Z\)
\(\Rightarrow2n+3⋮7\)
\(\Rightarrow2\left(n-2\right)+7⋮7\)
\(\Rightarrow n-2⋮7\)
\(\Rightarrow n=7k+2\left(k\in Z\right)\)
