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Homework Help: Int (e^cost)(sin2t)dt Ahhh

  1. Jul 5, 2010 #1
    Int (e^cost)(sin2t)dt Ahhh!!

    1. The problem statement, all variables and given/known data
    First make a substitution and then use integration by parts

    2. Relevant equations
    INTEGRAL OF (e^cost)(sin2t)dt

    3. The attempt at a solution

    the 2t is bothering me.

    try subbing u=e^cost

    thank you.
  2. jcsd
  3. Jul 5, 2010 #2


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    Science Advisor

    Re: Int (e^cost)(sin2t)dt Ahhh!!

    I would not use e^cos t. I would use the trig identity, sin(2t)= 2sin(t)cos(t) so that the integral became [itex]2\int e^{cos(t)}cos(t)sin(t)dt[/itex] and use the substitution u= cos(t), then integration by parts.
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