Question

9,-81, 729,-6561... What is the common ratio? Help which is the correct answer?

Answer 1

Answer:

$r = -9$

Step-by-step explanation:

Given

$Sequence: 9,-81, 729,-6561...$

Required

Determine the common ratio

The common ratio r is calculated using:

$r = \frac{T_n}{T_{n-1}}$

Let $n = 2$

So, we have:

$r = \frac{T_2}{T_{2-1}}$

$r = \frac{T_2}{T_1}$

From the sequence:

$T_2 = -81$

$T_1=9$

So, the equation becomes

$r = \frac{-81}{9}$

$r = -9$