Question

Aflati toate numerele naturale care impartite la 9 dau catul egal cu patratul restului

Answer 1

[tex]x:9=r^2\ rest\ r\ \textless \ =\ \textgreater \ x=9r^2+r, unde\ r\ \textless \ 9\\ r\ \textless \ 9=\ \textgreater \ r\in\{0,1,2,3,4,5,6,7,8}\\ r=0=\ \textgreater \ x=0+0=0\\ r=1=\ \textgreater \ x=9+1=10\\ r=2=\ \textgreater \ x=38\\ ....\\ r=8=\ \textgreater \ x=584\\ Numere\ cautate\ sunt \: 0,10,38,84,148,230,330,448,584. [/tex]