How Do You Prove the Limit of (2n+1)/(n+1) as n Approaches Infinity?

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Prove that the limit when x--> infinite of (2n+1)/(n+1) =2
So for ε > 0,exists N>0 so that n>N => |x -a|< ε
What I do is | (2n+1)/(n+1) |< ε, I do the math actions and I have |-1/(n+1)| < ε... NOW,what I don't get,when I remove the absolute value,do I get 1/(n+1)<ε or NOT?
 
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I believe you want to use this definition :

[itex]\forall \epsilon>0, \exists N | n>N \Rightarrow |a_n - L| < \epsilon[/itex]

So what is [itex]|a_n - L|[/itex]? Plug in your info and start massaging it into a suitable expression.
 
I know what to do,I just want to know if the part when I remove the absolute value is correct :)
 
Elaia06 said:
Prove that the limit when x--> infinite of (2n+1)/(n+1) =2
So for ε > 0,exists N>0 so that n>N => |x -a|< ε
What I do is | (2n+1)/(n+1) |< ε,
This is incorrect. You should start with
|(2n + 1)/(n + 1) - 2| < ε

It looks like the above is what you were working with, but didn't write it correctly.
Elaia06 said:
I do the math actions and I have |-1/(n+1)| < ε... NOW,what I don't get,when I remove the absolute value,do I get 1/(n+1)<ε or NOT?
Yes.
Elaia06 said:
I know what to do,I just want to know if the part when I remove the absolute value is correct :)