Question

calcule a soma dos 50 primeiros termos da pa (3,8...)?? por favor

Answer 1

$r = 5 a_n = a_1 + (n-1).r a_5_0 = 3 + (50-1).5 a_5_0 = 248 \\ S_n = \frac{(a_1 + a_n).n}{2} S_5_0 = \frac{(3 + 248).50}{2} S_5_0 = 6275$