Convergence of a Sequence

1. Mar 29, 2008

workerant

[SOLVED] Convergence of a Sequence

1. The problem statement, all variables and given/known data
Consider the following "recursively defined" sequence:

a1=0.3
a(n+1)=sqrt (an+1)

Compute the first first five terms and prove that it converges. Then, find the limit of the sequence.

Problem 3, particularly parts c and d here for the complete problem:

http://rutcor.rutgers.edu/~ngoldberg/math152/ws0837.pdf

3. The attempt at a solution

I would try to show that the sequence is increasing and bounded because that shows that it converges. I am not sure, however, how to go about doing this.

I think I am okay with finding the first five terms. I suppose the second term would be a2= sqrt (a1+1)=sqrt (1.3) and so on and so forth and it would get quite complicated.

I am not sure how to go about the proof and finding the limit.

Thank you.

2. Mar 29, 2008

tiny-tim

Welcome to PF!

Hi workerant! Welcome to PF!

Do one step at a time!

First step is to prove that a_n+1 > a_n.

In other words, that √(1 + a_n) > a_n

Hint: what is the condition for √(1 + a) > a?
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