Răspunsuri

2014-10-03T21:28:27+03:00
S=5+10+15+...+2005
s=2005+2000+...+5
----------------------------------
2s=2010+2010+...+2010
s=2010·401:2
s=403005
(1+3+5+...+2005)-1=1002X1002-1=1004003
SCUZE ERA 1003X1003-1=1006008
multumesc
da-mi te rog cel mai bun raspuns
multumesc
2014-10-03T21:30:49+03:00


5+10+15+...+2005=5*(1+2+3+...+401)=5*(401*402impartit la 2)=5*(401*201)=403005

sigur am gresit nu are cum sa dea asa suma mare...

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