[tex]Fie~x\in [n,8), deci:\\
n \leq x \leq 8\\
Cum~ 7~ este~ cel~ mai ~mare~ numar~ natural~ mai~ mic ~decat ~8~, adica: \\
7\ \textless \ 8, inseamna ~ca ~7~\in[n,8), adica: \\
n \leq 7\ \textless \ ~8 ~si ~cum ~in ~enunt ~se ~spune ~ca~ ''n''~ este~''\bold{singurul}~numar~\\natural~din~intervalul~ [n,8)'', \to ~\to~\to ~\boxed{\boxed{n=7}}[/tex]
