`[75]`
`M = (3x-1)/(x+1) in ZZ`.
`-> 3x - 1 vdots x + 1`
`-> 3x + 3 - 4 vdots x + 1`
`-> -4 vdots x + 1`
`-> x +1 in Ư(4)`
`-> x in {0, -2, 1, -3, 3, -5}`.
[75][75]
M=3x−1x+1∈ZM=3x-1x+1∈ℤ.
→3x−1⋮x+1→3x-1⋮x+1
→3x+3−4⋮x+1→3x+3-4⋮x+1
→−4⋮x+1→-4⋮x+1
→x+1∈Ư(4)→x+1∈Ư(4)
→x∈{0,−2,1,−3,3,−5}→x∈{0,-2,1,-3,3,-5}.