Question

Calcule a soma da PG infinita (1, 1/10, 1/100)

Answer 1

(use a formula da soma s=a1/an) eu nao tenho certeza se é essa 

Answer 2

Temos então (1, $\displaystyle\frac{1}{10},\frac{1}{100},\frac{1}{1000},...,\frac{1}{10^n}$)

Temos a formula da soma $Sn=\displaystyle\frac{a_1.(q^n-1)}{q-1}$

$Sn=\displaystyle\frac{1.((\frac{1}{10})^n-1)}{\frac{1}{10}-1}$

$Sn=\displaystyle\frac{(\frac{1}{10})^n-1}{(\frac{1}{10})-1}$

$Sn=\displaystyle\frac{(\frac{1}{10})^n-1}{(-\frac{9}{10})}$

$Sn=\displaystyle-\frac{10}{9}.(\frac{1}{10})^n+\frac{10}{9}$


Fica com Deus!!!