Question

2+4+6+...+2006=?
Vreau rezolvarea completa ! Ofer 20 p ! :) :)  Urgent~ :O

Answer 1

2+4+6+...+2006 =
= 2(1+2+3+...+1003)
1+2+3+...+1003 (aflam cu suma lui Gauss : n(n+1)/2)
=1003(1003+1)/2

2 × (1003×1004)/2 = 1003 × 1004 = 1.007.012