# A geometric sequence is defined by the explicit formula a_n = 3(-5)^(n-1), what is the recursive formula for the nth term of this sequence?

Jan 5, 2017

a_1=3; a_(n+1)=a_n(-5)

#### Explanation:

The first term (${a}_{1}$) is 3.

The second one (${a}_{2}$) is obtained by multiplyng $3 \cdot \left(- 5\right)$

The third one (${a}_{3}$) by multiplying $3 \cdot \left(- 5\right) \left(- 5\right) = {a}_{2} \cdot \left(- 5\right)$

and so on.

Then

a_1=3; a_(n+1)=a_n(-5)