Question

Quantos termos tem a PG(10, 20, ... 5120)

Answer 1

Boa noite!

Dados;

A1 → 10

N → ?

An → 5120

Q → a2/a1 → 20/10 = 2

_______________________________

An=a1·q⁽ⁿ⁻¹⁾

5120=10·2⁽ⁿ⁻¹⁾

5120/10=2⁽ⁿ⁻¹⁾

512=2⁽ⁿ⁻¹⁾

2⁹=2⁽ⁿ⁻¹⁾

9=n-1

-n=-1-9

-n=-10 (-1)

n=10

Att;Guilherme Lima