Answer:
a n= - 3a_{n-1}a n−1 with a₁ = - 0.3
Explanation:
The recursive formula for a geometric sequence is of the form
a_{n}a
n = ra_{n-1}a
n−1
where r is the common ratio
r = \frac{a_{2} }{a_{1} }
a
1
a
2
= \frac{0.9}{-0.3}
−0.3
0.9
= - 3 , thus
a_{n}a
n
= - 3a_{n-1}a
n−1
with a₁ = - 0.3