ma ajutati la acesc exercitiu : +8-4-9+7-1-2-4-5+7-3+2+6+1

Răspuns :

+8-4-9+7-1-2-4-5+7-3+2+6+1
=4-2-3-9+4+8+1
=2-12+12+1
=2+1
=3
4-9+7-1-2-4-5+7-3+2+6+1
2-1-2-4-5+7-3+2+6+1
-10+7-3+2+6+1
-4+6+1
3