Respuesta :

Answer+Step-by-step explanation:

First term a₁ = -1215   (Given)

…………………………………

Second term a₂ :

[tex]a_{2}=a_{2-1}\times \frac{1}{3} =a_{1}\times \frac{1}{3} =\frac{-1215}{3} =-405[/tex]

…………………………………

Third term a₃ :

[tex]a_{3}=a_{3-1}\times \frac{1}{3} =a_{2}\times \frac{1}{3} =\frac{-405}{3} =-135[/tex]

…………………………………

Fourth term a₄ :

[tex]a_{4}=a_{4-1}\times \frac{1}{3} =a_{3}\times \frac{1}{3} =\frac{-135}{3} =-45[/tex]