Respuesta :

Answer:

The common ratio of the geometric sequence is:

[tex]r=-2[/tex]

Step-by-step explanation:

A geometric sequence has a constant ratio 'r' and is defined by

[tex]a_n=a_1\cdot r^{n-1}[/tex]

where

  • aₙ is the nth term
  • a₁ is the first term
  • r is the common ratio

Given the sequence

[tex]-2,\:4,-8,\:16,\:-32,\:...[/tex]

Compute the ratios of all the adjacent terms:  [tex]r=\frac{a_n+1}{a_n}[/tex]

[tex]\frac{4}{-2}=-2,\:\quad \frac{-8}{4}=-2,\:\quad \frac{16}{-8}=-2,\:\quad \frac{-32}{16}=-2[/tex]

The ratio of all the adjacent terms is the same and equal to

[tex]r=-2[/tex]

Therefore, the common ratio of the geometric sequence is:

  • [tex]r=-2[/tex]