Limit of a Sequence: Does Square or Sqrt Change It?

  • Thread starter Thread starter Karl Porter
  • Start date Start date
  • Tags Tags
    Limit Sequence
Karl Porter
Messages
31
Reaction score
5
Homework Statement
I was curious, if I have a sequence that has a limit of 1
Relevant Equations
Lim an=1 as n tends to inf
Lim of an^2=1 as n tends to inf
Does the square of the sequence also have a limit of 1. Does the square root also equal 1? I've been trying to find some counterexamples but I think the limit doesn't change under these operations?
 
Physics news on Phys.org
Karl Porter said:
Homework Statement:: I was curious, if I have a sequence that has a limit of 1
Relevant Equations:: Lim an=1 as n tends to inf
Lim of an^2=1 as n tends to inf

Does the square of the sequence also have a limit of 1. Does the square root also equal 1? I've been trying to find some counterexamples but I think the limit doesn't change under these operations?
Can you think of a basic theorem of limits that would lead to a one line proof?

Hint: If ##\lim_{n \rightarrow \infty} a_n = L_a## and ##\lim_{n \rightarrow \infty} b_n = L_b##, then ...
 
  • Informative
  • Like
Likes pbuk and berkeman
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top