b=2004+2·(1+2+3+....+2003)este patratul unui numar natural

Răspuns :

2004+2{[2013(2013+1)]:2} 2004+2[(2013 • 2014):2] 2004+2(2013 •1007) 2004 +(2013 •1007 )
[tex]B=2004+2(1+2+3+...+2003)=2004+2* \frac{2003(2003+1)}{2} = [/tex][tex]=2004+2003*2004=2004(1+2003)=2004*2004= 2014^{2}[/tex][tex]= 4016016[/tex]

B=4016016 este patratul numarului 2004