Increasing or Decreasing Sequence

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Homework Help Overview

The discussion revolves around a recursively defined sequence, where the first term is given as a1 = 1, and subsequent terms are defined by an+1 = 1/(2 + an). Participants are exploring whether this sequence is increasing or decreasing, as well as its convergence properties.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are examining the terms of the sequence to determine its behavior, with some noting inconsistencies in whether terms increase or decrease. Questions about the correct interpretation of the recursive definition are raised, particularly regarding the order of operations.

Discussion Status

The discussion is ongoing, with some participants suggesting that the sequence may not be strictly increasing or decreasing. There is a focus on clarifying the sequence's definition and exploring its convergence, with no clear consensus yet on its behavior.

Contextual Notes

There is a noted concern about the formatting of the sequence definition, which may affect participants' understanding and analysis. The original poster expresses uncertainty about the implications of the sequence's behavior on its convergence.

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A sequence (an) is defined recursively by a1 =1 and an+1 = 1/ 2+an for all n is greater than 1 or equal 1.

ı'll prove that this sequence is convergent,buy ı cannot decide whethet it is increasing or decreasing .When ı write terms ,some terms increase some terms decrease.
 
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What are the first couple of terms that you got? From the definition in your post it seems like the sequence is increasing to me
 
a1=1/3,a2=7/21,a3=3/7,a4=7/17,a5=17/41 ...

according to my calculation, a1>a2, a3>a2, a5>a4, a3>a4

How can ı decide?
 
I suspect that your OP is not very well formatted now. Is the sequence
an+1 = (1/2)+an (which is what you wrote using proper order of operations)

or is it

an+1=1/(2+an)
which seems to match your most recent post

If it's the latter, then just like you described in your post it's neither increasing nor decreasing
 
My sequence is the second one.If it is neither increasing or decreasing ,how will ı show that it is convergent sequence? ı think there is a problem about sequence.

Thank you for efforts :)
 

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