Question

Stiti sa rezolvati orice de aici? Va rog e foarte important

Answer 1

[tex]a_1+a_2+...+a_{49}=50\\ a_1+a_1+r+a_1+2r+...+a_1+48r=50\\ 49a_1+r(1+2+...+48)=50\\ 49a_1+4\cdot \frac{(1+48)\cdot48}{2} =50\\ 49a_1+49\cdot96=50\\ 49a_1=50-4704\\ 49a_1=-4654\\ a_1=-4654/49[/tex]