Respuesta :
[tex] a_n=5\left(-\dfrac{1}{8}\right)^{n-1}\\\\a_1=5\left(-\dfrac{1}{8}\right)^{1-1}=5\left(-\dfrac{1}{8}\right)^0=5\\\\\text{The recursive formula:}\\\\a_n=\left\{\begin{array}{ccc}a_1=5\\a_{n+1}=-\dfrac{1}{8}a_{n}\end{array}\right [/tex]
The recursive formula for the geometric sequence is [tex]\rm a_n_+_1= \dfrac{-1}{8}a_n[/tex].
Given that
The geometric sequence with this explicit formula;
[tex]\rm a_n= 5\times \dfrac{-1}{8}^{(n-1)}[/tex]
We have to determine
The recursive formula for the geometric sequence.
According to the question
The recursive formula for the geometric sequence is determined in the following steps given below.
The geometric sequence with this explicit formula;
[tex]\rm a_n= 5\times \dfrac{-1}{8}^{(n-1)}[/tex]
Then,
For the recursive formula substitute n= 1,
[tex]\rm a_n= 5\times \dfrac{-1}{8}^{(n-1)}\\\\\rm a_1= 5\times \dfrac{-1}{8}^{(1-1)}\\\\\rm a_1= 5\times \dfrac{-1}{8}^0\\\\\rm a_1= 5\times 1\\\\\rm a_1= 5[/tex]
Therefore,
The recursive formula for the geometric sequence is,
[tex]a_n_+_1= \dfrac{-1}{8}a_n[/tex]
Hence, the recursive formula for the geometric sequence is [tex]\rm a_n_+_1= \dfrac{-1}{8}a_n[/tex].
To know more about Geometric sequence click the link given below.
https://brainly.com/question/11394972