Finding Limit of Sequence: Determine if Exists & Find Solution

[Fairy111]

Homework Statement

Determine whether the following sequence has a limit. Find the limit if it exists.

Homework Equations

a(n)=cos[n/(2^n)]

The Attempt at a Solution

Im not sure how to go about finding the limit...do i use l'hospital's rule?

 

[NoMoreExams]

When talking about limits you usually specify limit as n approaches something, do you mean infinity?

 

[Fairy111]

It doesn't actually say in the question, so i am assuming it means as n tends to infinity.

 

[HallsofIvy]

It should be obvious that n/2^n goes to 0 as n goes to infinity. Then use the fact that cos(x) is a continuous function.