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Homework Help: Antiderivative trig function

  1. Apr 19, 2008 #1
    Hey guys!
    So i have to find the antiderivative of
    (1-cos(t/6))^3 * sin(t/6)
    I have tried a bunch of different ways like by parts, trig substitution, identities, u-substitution then developing it, etc. but i just cant get it!!
    Can some one just tell me the proper method to use after that im sure i can figure it out.
    thanks!!!
     
  2. jcsd
  3. Apr 19, 2008 #2

    Dick

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    You must not have tried u substitution very hard. Try u=(1-cos(t/6)).
     
  4. Apr 19, 2008 #3

    Defennder

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    It should be doable. Or so says Wolfram's online integrator. I tried it out and managed to reduce it to a doable trigo form. You only need use integration by parts and then replace all those trig terms which are of power 2 and 3 with power 1 terms by means of some trigo formulae.
     
  5. Apr 19, 2008 #4

    Dick

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    I don't see why you are working so hard on it. There's a much simpler way.
     
  6. Apr 19, 2008 #5

    Defennder

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    You're right, I just didn't see it before you posted.
     
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