183k views
4 votes
Find the fifthterm in the geometricsequence, given the first term and the common ratioa1 = 5 and r = -3a5=?

User Udarts
by
8.2k points

1 Answer

4 votes

Given: A geometric sequence with first term and the common ratio a1 = 5 and r = -3.

Required: Fifth term of the geometric series.

Step-by-step explanation:

In a geometric sequence, with first term 'a' and common ratio 'r'

nth term is


a_n=ar^(n-1)

So the fifth term is


a_5=ar^4

a = 5 and r = - 3.

So


\begin{gathered} a_5=(5)(-3^)^4 \\ a_5=5(81) \end{gathered}

So


a_5=405

Final Answer: The fifth term of Geometric sequence is 405.

User Doris Liu
by
8.0k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories