2 + 4 + 6 + ......... + 2 014 = 1 015 056
= 2 × ( 1 + 2 + 3 + ........ + 1 007 ) = → am dat factor comun pe 2
1 + 2 + 3 + .... + 1 007 = → aplic formula sumei lui Gauss
= 1 007 termeni × ( 1 + 1 007 ) / 2 =
= 1 007 x 1008 / 2 =
= 1007 × 504 =
= 507 528
________________
= 2 × 507 528 =
= 1 015 056
