Đáp án:
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Giải thích các bước giải:
`a,n+13 \vdots n+7`
`\to (n+7) +6 \vdots n+7`
`\to 6 \vdots n+7`
`\to n+7 ∈Ư(6)`
`\to n+7 ∈{1,-1,2,-2,3,-3,6,-6}`
`\to n∈ {-6,-8,-5,-9,-4,-10,-1,-13}`
Vậy `n∈{-6,-8,-5,-9,-4,-10,-1,-13}`
,
`b,n-7 \vdots n+5`
`\to (n+5) -12 \vdots n+5`
`\to -12 \vdots n+5`
`\to n+5∈Ư(-12)`
`\to n+5∈{1,-1,2,-2,3,-3,4,-4,6,-6,12,-12}`
`\to n∈{-4,-6,-3,-7,-2,-8,-1,-9,1,-11,7,-17}`
Vậy `n∈{-4,-6,-3,-7,-2,-8,-1,-9,1,-11,7,-17}`
,
`c,2n+13 \vdots n+5`
`\to 2n+10+3 \vdots n+5`
`\to 2(n+5)+3 \vdots n+5`
`\to 3 \vdots n+5`
`\to n+7 ∈Ư(3)`
`\to n+7∈{1,-1,-3,3}`
`\to n∈{-6,-8,-10,-4}`
Vậy `n∈{-6,-8,-10,-4}`
,
`d,5n+45 \vdots n+3`
`\to 5n+15+30 \vdots n+3`
`\to 5(n+3)+30 \vdots n+3`
`\to 30 \vdots n+3`
`\to n+3 ∈Ư(30)`
`\to n+3∈{1,-1,2,-2,3,-3,5,-5,6,-6,10,-10,15,-15,30,-30}`
`\to n∈ {-2,-4,-1,-5,0,-6,2,-8,3,-9,7,-13,12,-18,17,-33}`
Vậy `n∈ {-2,-4,-1,-5,0,-6,2,-8,3,-9,7,-13,12,-18,27,-33}`
