a/ \(-22⋮n\)
\(\Leftrightarrow n\inƯ\left(-22\right)\)
\(\Leftrightarrow n\in\left\{1;-1;2;-2;11;-11;22;-22\right\}\)
Vậy ...
b/ \(n+19⋮18\)
\(\Leftrightarrow n+9\in B\left(18\right)\)
Vậy ..
c/ \(9⋮n+1\)
\(\Leftrightarrow n+1\inƯ\left(9\right)\)
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