Răspuns :
|. (2-1)+(4-3)+(6-5)+(8-7)+(10-8)+(12-10) = 8
||. (2-1)+(4-3)+(6-5)+(12-7)+(8-8)+(10-10) = 8
||. (2-1)+(4-3)+(6-5)+(12-7)+(8-8)+(10-10) = 8
a = 2 + 4 + 6 + 8 +10 + 12
-1 - 3 - 5 - 7 - 8 - 10
a = 1 + 1 +1 + 1 + 2 + 2 = 8
-1 - 3 - 5 - 7 - 8 - 10
a = 1 + 1 +1 + 1 + 2 + 2 = 8