Răspuns:
Explicație pas cu pas:
a)x+1 ∈{1,3,6} |-1
x∈{0,2,5}
b)2x+1∈{1,3,9} |-1
2x∈{0,2,8} |:2
x∈{0,1,4}
c) x+1|x+1
x+1|x+3
se scad cele 2 relatii
x+1|x+3-x-1
x+1|2
x+1∈{1,2}
x∈{0,1}
d) x|x+5
x|x
x|x+5-x
x|5
x∈{1,5}
