Răspuns :
Răspuns
4/15 < 4/n <=> 4*n < 4*15 <=> n < 15
4/n < 1/3 <=> n*1 > 4*3 <=> n > 12
=> n = {13, 14}
Explicație pas cu pas:
[tex]\it \dfrac{4}{15}<\dfrac{4}{n}<\dfrac{^{4)}1}{\ 3} \Rightarrow \dfrac{4}{15}<\dfrac{4}{n}<\dfrac{4}{12} \Rightarrow 12<n<15\Rightarrow n\in\{13,\ 14\}[/tex]