154-153+152-151+150-149+.....+4-3+2-1

Răspuns :

154-153+152-151+150-149+.....+4-3+2-1=
=(154-153)+(152-151)+(150-149)+...(4-3)+(2-1)=
=77

Sper ca te-am ajutat. Succes!
154-153+152-151+150-149+.....+4-3+2-1 =
grupam scaderile
= (154-153) + (152-151)+(150-149)+...+(4-3)+(2-1) =
= 1 + 1 + 1 + 1 +...+ 1 + 1 (de 154:2 = 77 ori)
= 1 × 77 =
= 77