[tex]\hbox{O fractie este ireductibila atunci cand nu mai poate fi simplificata.} \\ \hbox{-2 numere consecutive sunt intotdeauna prime intre ele-} \\\\ \frac{7n+1}{7n} - \in N* \\ n \in N* \\\\\\ \Longrightarrow 7n|(7n+1) \\\\ 7n|7n \\\\\\ 7n|(7n+1-7n) \\\\ 7n|1 \\\\ n|1 \longrightarrow n=1[/tex]
