N=2003(2004(9+8+7+...+2)+2015)+1
Dat A=9+8+7+...+2
A có số số hạng là (9-2)*1+1=8 so hang
A=(9+2)*8/2=44
N=2003(2004*44+2005)+1
N=2003*(88176+2005)+1
N=2003*90181+1=180632543+1=180632544
số to quá
DUYỆT NHA
2004N=2003(2004^10+2004^9+...+2004^2+2004^1)+2004
2004N-N=2003(2004^10-1)+2003
2003N=2003(2004^10-1+1)
N=2003:2003(2004^10)
N=2004^10