Question

Determina valorile nr nat n astfel incat (n+1) divide (3n + 11 ).

Answer 1

n+1|3n+11
stim ca n+1|n+1  ,   x3
             n+1|3(n+1)

din n+1|3n+11
      n+1|3n+3,  n+1 divide si diferenta lor
=>  n+1|8
n+1={1,2,4,8}
=>n={0,1,3,7}