Question

usando o metodo de Glauss, calcule a soma 1+3+5+7...+97+99

Answer 1

A1 = 1 r = 2 An = 99 Sn = ? An = A1 + (n - 1).r 99 = 1 + (n - 1).2 99 = 1 + 2n - 2 99 + 1 = 2n 2n = 100 n = 100/2 n = 50 Sn = (A1 + An).n/2 Sn = (1 + 99).50/2 Sn = 5000/2 Sn = 2500