Após os calculo chegamos ao resultado que o oitavo termo da Progressão Geométrica:

[tex]\large \text {$a8 = \dfrac{1}{243} $}\\\\\\[/tex]

                                [tex]\Large\text{$ Progress\tilde{a}o ~Geom\acute{e}trica $}[/tex]

Encontrar a razão da PG.

[tex]\large \text {$ q = \dfrac{a2}{a1} $}\\\\\\\large \text {$q = \dfrac{3}{9} $}\\\\\\\large \text {$q = \dfrac{1}{3} $}\\\\[/tex]

Encontrar o valor do oitavo termo da PG.

[tex]\large \text {$an = a1 ~. ~q^{n - 1} $}\\\\\\\large \text {$a8 = 9 ~. ~(\dfrac{1}{3})^{8 - 1} $}\\\\\\\large \text {$a8 = 9 ~. ~(\dfrac{1}{3})^{7} $}\\\\\\\\\large \text {$a8 = 9 ~. ~\dfrac{1}{2187} $}\\\\\\\large \text {$a8 = \dfrac{9}{2187} $}\\\\\\\large \text {$a8 = \dfrac{1}{243} $}\\\\\\[/tex]

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