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Math Help - Quite easy integration, but can't make it work!

  1. #1
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    Question Quite easy integration, but can't make it work!

    What is the integral of: (4sin(x))/(2+cos(x)) . Thank you.
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  2. #2
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    Have you learned U-substitution? Always try to pull out some constant to make the integrand simpler. In this case 4 can be pulled out and from there it's a simple u-substitution with 2 + cos(x) = u, du = -sin(x). Can you take it from here?
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  3. #3
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    Quote Originally Posted by charlie8529 View Post
    What is the integral of: (4sin(x))/(2+cos(x)) . Thank you.
      \int {\frac{{4\sin x.dx}}<br />
{{2 + \cos x}}}  \hfill \\

     {\text{Let  }}2 + \cos x = u \hfill \\

     - \sin x.dx = du \hfill \\

    now finish it

    answer =  - 4\log \left( {2 + \cos x} \right) + c \hfill \\
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  4. #4
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    I've got a whole sheet of these to do, please could you finish off this one so i can have a worked example to make sure i do it right. Thank you.
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