Question

calculati suma 2+4+6+8+....+200

Answer 1

Răspuns:

Explicație pas cu pas:

2+4+6+8+......+200 = 2·(1+2+3+4+....+100) = 2·(1+100)·100:2 =

= 101·100 = 10100

Answer 2

Gauss

1 + 2 + .. + n = n·(n + 1)/2

S = 2 + 4 + .. + 200

S  = 2·(1 + 2 + .. + 100)

S = 2·100·101/2

S = 100·101

S = 10100