Question

3) Determine a soma dos 50 primeiros termos da PA a seguir: (5, 10, 15, ...). Use as fórmulas a seguir: a = a1 + (n - 1) (a1 + ann Sn = 2
a) 6375
b) 6390
c) 6363
d) 6380
e) 6300​

Answer 1

Resposta:

sla

Explicação passo a passo:

Answer 2

Resposta:

Letra A

Explicação passo a passo:

$r=10-5=5\\\\a_n=a_1+r(n-1)\\\\a_5_0=a_1+5(50-1)\\\\a_5_0=5+5.49\\\\a_5_0=5+245\\\\a_5_0=250\\\\S_n=\frac{(a_1+a_n)n}{2} \\\\S_+n=\frac{(5+250).50}{2}\\\\S_5_0=\frac{255.50}{2}\\\\S_5_0=255.25\\\\S_5_0=6375$