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    I need help with the above questions please guys! Thanks! =)
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    (Original post by Delta, Δ)
    I need help with the above questions please guys! Thanks! =)
    Integrate by parts.
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    I don't Think integration by parts will work since you end up vetting the integral of e^xsinx at some point.

    If you are familiar with demoivres theorem then that Is one way. I'd be surprised if they gave that question in a normal core paper without external help.
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    You do it by parts.

    Reach your original integral.

    Let I = e^x cosx

    And solve for I
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    (Original post by BankOfPigs)
    I don't Think integration by parts will work since you end up vetting the integral of e^xsinx at some point.

    If you are familiar with demoivres theorem then that Is one way. I'd be surprised if they gave that question in a normal core paper without external help.
    Wolfram Alpha says integration by parts. There's a trick to it though.
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    (Original post by rayquaza17)
    Wolfram Alpha says integration by parts. There's a trick to it though.
    I quite like the idea of recurring integrals.
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    Honestly, integration by parts: (Check spoiler after you have done integration by parts 1 time):

    Spoiler:
    Show

     \int {e^{x}cos(x) dx} = e^{x}cos(x) + \int {e^{x}sin(x) dx}

    What do you get when you preform integration by parts on   \int {e^{x}sin(x) dx} ?

    Is there anyway to simplify the expression we now have for \int {e^{x}cos(x) dx} ?
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    (Original post by BankOfPigs)
    I don't Think integration by parts will work since you end up vetting the integral of e^xsinx at some point.

    If you are familiar with demoivres theorem then that Is one way. I'd be surprised if they gave that question in a normal core paper without external help.
    This is a standard A level integration by parts question - no need for de Moivre. At some point you get an expression for your original integral in terms of itself, then you just rearrange and solve.
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    (Original post by davros)
    This is a standard A level integration by parts question
    I'm not sure about other Awarding Bodies but it was removed from the OCR specification over a decade ago. The endorsed textbook includes it as an asterixed question (beyond the scope of the course).
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    In a way I do wish the boards would state the exam specification simply in terms of a huge list of questions the candidate needs to be able to answer.
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    (Original post by Mr M)
    I'm not sure about other Awarding Bodies but it was removed from the OCR specification over a decade ago. The endorsed textbook includes it as an asterixed question (beyond the scope of the course).
    I await the day when quadratics with imaginary roots are considered beyond the scope of the course.
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    (Original post by Mr M)
    I'm not sure about other Awarding Bodies but it was removed from the OCR specification over a decade ago. The endorsed textbook includes it as an asterixed question (beyond the scope of the course).
    I was talking about 'real' A levels - not this silly modular nonsense
 
 
 
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