Răspuns:
Explicație pas cu pas:
a) n/3 < 2/3 <=> n < 2 => n ∈ {0 ; 1}
b) 7/4 > (4n+5)/4 <=> 7 > 4n+5 => 7-5 > 4n =>
2 > 4n => 1 > 2n => n < 1/2 => n = 0
c) 7/n > 7/2 ; n ≠ 0 => n = 1
d) 11/17 < 11/(5n+4) <=> 1/17 < 1/(5n+4) =>
5n+4 < 17 => 5n < 13 => n < 13/5 => n ∈ {0 ; 1 ; 2}