1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Reasonably simple integral

  1. Oct 30, 2009 #1
    1. The problem statement, all variables and given/known data
    1. Evaluate:
    [tex]\oint cos^2(x)dx[/tex]

    Using two different methods


    2. Relevant equations



    3. The attempt at a solution
    I have done it making the substitution of cos^2(x) = (1 + cos(2x))/2 but don't see how you can do this another way. Integration by parts doesn't seem to work and nor does substitution as far as I'm aware. Any ideas?
     
  2. jcsd
  3. Oct 30, 2009 #2
    You could maybe do something with this:

    [tex]cos^2(x) + sin^2(x) = 1[/tex]
     
  4. Oct 30, 2009 #3
    Integration by parts does indeed work on this integral, you just have to know where to use your trig identities as Seannation was hinting at.
     
  5. Oct 30, 2009 #4
    Ah ok I've got it now, thanks!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Reasonably simple integral
  1. Simple integral (Replies: 2)

  2. Simple integral or not? (Replies: 10)

  3. Is it reasonable? (Replies: 4)

  4. Simple integral (Replies: 1)

Loading...