Uncovering Periodicity of tan|x|: Rules & Examples

  • Context: Undergrad 
  • Thread starter Thread starter Bassalisk
  • Start date Start date
  • Tags Tags
    Periodic
Click For Summary

Discussion Overview

The discussion centers on the periodicity of the function tan|x|, exploring whether it is periodic and the rules for determining the periodicity of functions in general. Participants also reference other functions such as ln(sin(x)) and e^sin(x) in this context.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Mathematical reasoning

Main Points Raised

  • One participant questions the periodicity of tan|x| and seeks a rule for determining the periodicity of functions.
  • Another participant suggests finding a constant a such that f(x+a) = f(x) to explore periodicity.
  • Several participants mention plotting the graph of tan|x|, noting that it resembles tan(x) but ultimately concludes that tan|x| is not periodic.
  • There is a discussion about the symmetry of the graph, with one participant pointing out that while it has mirror symmetry around x=0, it lacks symmetry around other points, which affects its periodicity.
  • One participant expresses confusion about the concept of periodicity but later indicates a better understanding after the discussion.

Areas of Agreement / Disagreement

Participants generally agree that tan|x| is not periodic, but there is some confusion and differing interpretations about the implications of its graph and symmetry.

Contextual Notes

Participants reference the need for a clear definition of periodicity and the role of symmetry in determining it, but these concepts remain somewhat unresolved in the discussion.

Bassalisk
Messages
946
Reaction score
2
Is tan|x| periodic and if not, why not?


I just found in my book that tan|x| isn't periodic, and how do we make up a rule how to seek periodicity of functions.

I.e.

ln(sin(x)), e^sin(x)... etc
 
Physics news on Phys.org
Find a constant a such that f(x+a) = f(x). So basically you can solve for a function a(x) here, and make sure its a constant function.
 
Plot the graph. Notice that if you erase the coordinate axes you can still see where the origin must lie.
 
jambaugh said:
Plot the graph. Notice that if you erase the coordinate axes you can still see where the origin must lie.

I did plot the graph, that's why i got confused. I saw a lot of functions, resembling tan(x). I got the feeling that it was periodic, but actually tan|x| isn't.
 
Bassalisk said:
I did plot the graph, that's why i got confused. I saw a lot of functions, resembling tan(x). I got the feeling that it was periodic, but actually tan|x| isn't.

Look at the graph closely. It should have a mirror symmetry around x=0. But notice it is not mirror symmetric around any other point. So you can't shift the graph through a period so it looks exactly the same.
 
jambaugh said:
Look at the graph closely. It should have a mirror symmetry around x=0. But notice it is not mirror symmetric around any other point. So you can't shift the graph through a period so it looks exactly the same.

Thank you I understand now. I had bad view of what it means to be periodic.
 

Similar threads

  • · Replies 33 ·
2
Replies
33
Views
4K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 8 ·
Replies
8
Views
4K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 8 ·
Replies
8
Views
1K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 12 ·
Replies
12
Views
2K