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Homework Help: Integral of tangent squared of x

  1. Dec 11, 2005 #1
    I tried and tried and I'm not able to solve this. I've managed to find the integral of sin squared of x by using the fact that cos(2x)=1-2(sin(x))^2, but I'm not able to do the same for tangent because I'm stuck with a quotient.
     
  2. jcsd
  3. Dec 11, 2005 #2

    Galileo

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    Have you ever seen the term tan^2(x) in a derivative of some function? Recognizing this may put you on the right track.
     
  4. Dec 11, 2005 #3
    well since
    1 + (tan(x))^2 = (sec(x))^2

    and we know that the derivative of tan(x) is (sec(x))^2

    then it's easy to find the integral of (tan(x))^2
     
  5. Dec 11, 2005 #4

    Hurkyl

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    I've merged your two threads.

    P.S.: What "quotient" did you get that you were having trouble integrating? If I could see it, maybe I could give a hint on how to integrate it.

    P.P.S.: people learn better when you give them hints, or direction on the problem than when you do most of the steps for them and just leave a short blank at the end. :grumpy:
     
    Last edited: Dec 11, 2005
  6. Dec 11, 2005 #5
    never mind, I was on the wrong track. What d_leet said was right, you need to use (sec(x))^2
     
  7. Dec 11, 2005 #6

    Hurkyl

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    I'm not so sure. You certainly weren't on the easy track, but I am not yet ready to believe you were on the wrong track.
     
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