Respuesta :

Answer:

Decreasing Geometric Sequence

Step-by-step explanation:

A geometric sequence is a sequence of non-zero numbers where each term after the first is found by multiplying the previous one by a fixed value. Here, we can multiply by 1/3 each time to get the next number, and out sequence is decreasing, so we have a DGS

Let's divide terms

[tex]\\ \sf\longmapsto r=\dfrac{405}{1215}=\dfrac{1}{3}[/tex]

[tex]\\ \sf\longmapsto r=\dfrac{135}{405}=\dfrac{1}{3}[/tex]

[tex]\\ \sf\longmapsto r=\dfrac{45}{135}=\dfrac{1}{3}[/tex]

It's a decreasing Geometric sequence