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Homework Help: Help with an integral please

  1. Mar 5, 2012 #1
    1. The problem statement, all variables and given/known data
    This is one of these AP free response questions divided into a,b,c,d,etc. but im just going to ask for a small part of the problem.

    I need to integrate y=7tecost






    3. The attempt at a solution

    I tried using U substitution but it didn't work. I tried things like the following:

    Integrate with respect to t (dt).

    make ecost=u and t=-cosln(t)



    but it seems I am complicating my life. Any tips?
     
  2. jcsd
  3. Mar 5, 2012 #2

    LCKurtz

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    I would feel very safe telling you there is no elementary antiderivative for that function. My best guess would be it was supposed to be$$
    \int (7\sin t) e^{\cos t}\, dt$$which would be straightforward.
     
  4. Mar 5, 2012 #3
    Yeah, I researched a bit around and for some reason this can only be done with a calculator (definite integral).

    Wonder how the computer/calculator does it actually.


    This was from the 2010 AP Calculus AB test
     
  5. Mar 5, 2012 #4

    LCKurtz

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    Well, your original post did not give a definite integral. That opens the door to numerical routines such as Trapezoidal or Simpson's rules.
     
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