Question

Qual é o valor da soma dos infinitos termos da PG (2/5,1/5,1/10,1/20,..)

Answer 1

$a_{1}= \frac{2}{5}$

$q= \frac{ \frac{1}{5} }{ \frac{2}{5} } = \frac{1}{5} . \frac{5}{2} = \frac{1}{2}$

$S= \frac{a_{1}}{1-q} =\frac{ \frac{2}{5} }{1- \frac{1}{2} }=\frac{ \frac{2}{5} }{\frac{1}{2} }= \frac{2}{5} . \frac{2}{1} = \frac{4}{5}$