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Homework Help: Have a question about integrals

  1. Oct 21, 2007 #1
    1. The problem statement, all variables and given/known data

    integrate (tan4x)^2.

    2. Relevant equations



    3. The attempt at a solution

    i have tried the box method but it won't work. i have also been told to do the integral b parts using dv, v, u, and du. i have heard of that method but the teacher insists on teaching the box method. is it possible with the box method.
     
  2. jcsd
  3. Oct 21, 2007 #2
    [tex]\int\tan^{2}{4x}dx[/tex]

    yes? ima start working on it. idk what the box method is. also, show some work or i won't post anything if i even get anywhere, lol.
     
  4. Oct 21, 2007 #3
    i have tried to convert that to the sin over cos and then integrating but i don't have any idea what to do after that
     
  5. Oct 21, 2007 #4
    dope! trig identity ...
     
  6. Oct 21, 2007 #5
    anybody else got it?? i really just want the steps getting to the answers not necessarily the answer
     
  7. Oct 21, 2007 #6

    rock.freak667

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    Homework Helper

    Hmmm....remember [tex]sec^2A=1+tan^2A[/tex] so if ever A=4x .....you can replace tan[tex]^2[/tex]4x with sec
     
  8. Oct 21, 2007 #7
    i told you!

    [tex]\int\tan^{2}{4x}dx=\int(\sec^{2}4x-1)dx[/tex]
     
  9. Oct 21, 2007 #8
    I'm simply wondering, what is the box method? I never heard of it.
     
  10. Oct 21, 2007 #9
    maybe it's the table method?
     
  11. Oct 22, 2007 #10
    here is my answer in the file

    i have added a file with my solution
     

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  12. Oct 22, 2007 #11
    your picture will have to be approved

    just post a link
     
  13. Oct 22, 2007 #12
    where can i upload it or an email adress to send it?

    you can also contact me using icq: 466921864

    i will send it to you
     
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