Evaluate the following infinite series or state that the series diverges. sum_{k=1}^infty4^{-3k}

Emily-Jane Bray

Emily-Jane Bray

Answered question

2020-11-23

Evaluate the following infinite series or state that the series diverges.
k=143k

Answer & Explanation

StrycharzT

StrycharzT

Skilled2020-11-24Added 102 answers

The given series can be written as
k=1(43)n=k=164n
This forms the geometric series where the first term we get by putting k=1 which will be
a=641=164
And the common ratio will be r=164
The geometric series is convergent when r<1 and here we have r=164 which is <1
The formula used to find the sum of the geometric series is
S=a1r (1)
Putting the values of a and r in equation (1) we get
S=1641164
S=163
therefore, the series is convergent

Jeffrey Jordon

Jeffrey Jordon

Expert2021-12-27Added 2605 answers

Answer is given below (on video)

Do you have a similar question?

Recalculate according to your conditions!

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?