Question

Calcule a soma dos 300 primeiros termos da P.A(1,5,9...)

Answer 1

an = a1+(n-1).r
a300 = 1+(300-1).4
a300 = 1+299.4
a300 = 1+1196
a300 = 1197

Answer 2

an=a1+(n-1).r
300=1+(300-1)4
300=1+299.4
300=1+1196
300=1197