Bună !
a₁
a₂=-10
a₃
a₄=-4
a₅
a₂=a₁+r=-10 a₁=-10-r
a₄=a₁+3r=-4 -10-r +3r=-4 2r=6 r=3 rezulta a₁=-10-3=-13
a₁=-13
a₃=-13+2*3=-7
a₅=-13+4*3=-1
