Răspuns:
6/(x+1)€Z rezultă că x+1€D6
D6={1,2,3,6,-1,-2,-3,-6}
x+1€{1,2,3,6,-1,-2,-3,-6}
x+1=1 ,x=1-1, x=0
x+1=2,x=2-1, x=1
x+1=3,x=3-1, x=2
x+1=6,x=6-1, x=5
x+1= -1, x= -1-1, x= -2
x+1= -2, x= -2-1, x= -3
x+1= -3, x= -3-1, x= -4
x+1= -6, x= -6-1, x= -7
A={0,1,2,5,-2,-3,-4,-7}