Question

aflati x apartine N astfel incat 3 supra x+1 apartine N

Answer 1

$\frac{3}{x+1}$ ∈ N => x+1 | 3 => (x+1)∈ $D_{3}$ = {1;3} (doar divizorii naturali, caci x∈N)
Avem:
x+1=1 =>x=0
x+1=3 =>x=2
Solutie: {0,2}