👤
a fost răspuns

problema 9, va rog!!!

Problema 9 Va Rog class=

Răspuns :

[tex]\text{Conform primei ipoteze:}\\ n+8m+8=mn+m\\ 8m-m+8=mn-n\\ 7m+8=n(m-1)\Rightarrow n=\frac{7m+8}{m-1}\in \mathbb{N}\\ \Rightarrow m-1|7m+8\\ \text{ Dar }m-1|m-1\Rightarrow m-1|7m-7 \\ \text{Rezulta din ultimele doua relatii }m-1|(7m+8-7m+7) \Rightarrow m-1|15\\ \Rightarrow m-1\in\{1,3,5,15\}\Rightarrow m\in\{2,4,6,16\} \\ m=2\Rightarrow n=22 \\ m+n=24,\ n^2+2n=n(n+2)=22\cdot24 \\ cmmdc=24[/tex]
[tex]\\ m=4\Rightarrow n=12 \\ m+n=16,\ n^2+2n=n(n+2)=12\cdot14 \\ cmmdc=8 \\ m=6\Rightarrow n=10 \\ m+n=16,\ n^2+2n=n(n+2)=10\cdot12 \\ cmmdc=8 \\ m=16\Rightarrow n=8 \\ m+n=24,\ n^2+2n=n(n+2)=8\cdot10 \\ cmmdc=8[/tex]
Asadar m=2,n=22